Abrasive article and method of forming same

Abstract

According to one aspect, an abrasive article includes: a backing; a primer, which covers the backing; an abrasive layer comprising abrasive particles and a binder; wherein the abrasive particles have a random rotational orientation; wherein the abrasive particles have a total height H and a fracture feature at a height of 55% H to 90% H. The fracture feature is configured to enable fracture when the particle has a front facing orientation with respect to the grinding direction by an amount greater than an amount of fracture when the particle is in a side facing orientation with respect to the grinding direction.

Description

Technical Field

[0001] The following relates to abrasive articles, and in particular to coated abrasive articles and methods of forming coated abrasive articles. Summary of the Invention

[0002] According to one aspect, an abrasive article includes: a backing; a make coat covering the backing; an abrasive layer comprising abrasive grains and a binder; wherein the abrasive grains have a random rotational orientation; wherein the abrasive grains have an overall height H and a fracture feature located at a height between 55% and 90% of H. The fracture feature is configured to fracture when the grains have a head-facing orientation relative to the grinding direction, with the fracture amount being greater than when the grains have a side-facing orientation relative to the grinding direction. BRIEF DESCRIPTION OF THE DRAWINGS

[0003] The present disclosure may be better understood, and its numerous features and advantages made apparent to those skilled in the art by referencing the accompanying drawings.

[0004] Figure 1A Includes images of abrasive particles with different rotational orientations relative to the grinding direction.

[0005] Figure 1B Including comparison with Figure 1A A graph of the grinding energy versus the cumulative material removed for an abrasive article having particles of different rotational orientations.

[0006] Figure 2A Included is an illustration of a top view of a portion of a coated abrasive article according to an embodiment.

[0007] Figure 2B Included is an illustration of a top view of a portion of a coated abrasive article according to an embodiment.

[0008] Figure 3 An exemplary image of a portion of an abrasive article including abrasive particles having randomly oriented abrasive particles.

[0009] Figure 4A Included is a side view illustration of abrasive particles on a backing according to an embodiment.

[0010] Figure 4B Included is a side view illustration of particles having oblique angles on a backing according to an embodiment.

[0011] Figure 4C include Figure 4B A top-down view of the particles.

[0012] Figure 4D Included is a side view illustration of particles having oblique angles on a backing according to an embodiment.

[0013] Figure 4E include Figure 4D A top-down view of the particles.

[0014] Figure 5A Included are perspective view illustrations of shaped abrasive particles according to embodiments.

[0015] Figure 5B Included are top-down view illustrations of shaped abrasive particles according to embodiments.

[0016] Figure 6A Included is an image of 3-PT star-shaped abrasive particles.

[0017] Figure 6B An illustration of a side view of a shaped abrasive particle is included in Figure 65A.

[0018] Figure 7 Included are perspective view illustrations of shaped abrasive particles according to embodiments.

[0019] Figure 8A Included is a perspective view illustration of controlled height abrasive particles according to an embodiment.

[0020] Figure 8B Included is a perspective view illustration of a non-shaped particle according to an embodiment.

[0021] Figure 9 Included are graphical representations of indentation curvature radii of abrasive particles according to embodiments.

[0022] Figure 10 Illustration of a perspective view of a 3-PT star-shaped abrasive particle including fracture features as described herein.

[0023] Figures 11A to 11G Includes images of modeled abrasive particles.

[0024] Figures 12A to 12G Includes images of modeled stresses in abrasive particles.

[0025] Figures 13A to 13G Includes images of modeled stresses in abrasive particles.

[0026] Figure 14 Included are plots of the radius of curvature for samples S5 and S6. DETAILED DESCRIPTION

[0027] The following relates to methods of forming abrasive articles, such as fixed abrasive articles, and more particularly, coated abrasive articles. These abrasive articles can be used in a variety of material removal operations on a variety of workpieces.

[0028] Figure 2AAn illustration of a portion of a coated abrasive article 200 according to an embodiment is included. As shown in FIG2 , the coated abrasive article 200 may include a backing 201 having a longitudinal axis 280 and a transverse axis 281 defining an abrading direction. The abrasive article 200 may include: a backing 201 having a major surface; and an abrasive layer forming an abrasive surface covering the major surface of the backing. The abrasive layer may form a single layer of abrasive grains 202 and 203 adhered to the major surface of the backing via a binder. Figure 2B Also included is an illustration of a portion of a coated abrasive having abrasive particles 202 and 203 .

[0029] It is known that the orientation of the particles has an impact on the fracture behavior and performance of the abrasive particles. Referring to Figure 1, the grinding behavior of particles with a front-facing orientation relative to the grinding direction is different from that of particles with a side-facing orientation. Over time, the grinding energy decreases as the front-facing particles break and wear. For side-facing particles, the opposite occurs; the grinding energy increases as the particles break and wear. Therefore, particles that break when used in a front-facing orientation but do not break when used in a side-facing orientation are desirable. Such particles can be placed and provide benefits regardless of their rotational orientation relative to the grinding direction.

[0030] In embodiments, abrasive grains can have a random rotational orientation relative to the grinding direction. The randomness of rotational orientation is assessed by creating a histogram or a distribution measuring orientation from a random sampling area of ​​a given abrasive article. The process for measuring the rotational orientation of the particles on the substrate begins with obtaining a coated abrasive sample that does not include a covering layer on the particle, or cleans a coated abrasive sample to expose the particle so that the particle is clearly visible. If the coated abrasive article includes a layer (such as, a multi-layer glue, a top glue, etc.) covering the particle, a gentle sandblasting operation can be carried out to selectively remove the covering layer and expose the abrasive grain below. During the sandblasting operation, care should be taken to ensure that the particle is not damaged or moved. The selective removal operation can be carried out in stages to ensure that only the covering layer is removed without damaging or changing the particle below.

[0031] After obtaining the sample of particle exposure, use suitable device, such as the CannonPowershot S110 camera with a resolution of 338 pixels / cm, to image at least two randomly selected areas of sample.According to these images, use MATLAB image analysis software that each particle is classified relative to the position and orientation of sample edge.The orientation of particle is based on the grinding direction of the expectation of abrasive article.All sample images should be evaluated using the same axis.The orientation of each particle is limited by the orientation angle between-90 degree and+90 degree.Then the orientation angle is plotted in the figure of orientation angle (x-axis) to frequency (y-axis), to create the histogram of orientation angle.If histogram has substantially flat profile, so that the frequency of any given orientation angle is almost identical with the frequency of any other orientation angle, then histogram shows that particle does not have main orientation mode roughly, and therefore, particle has random orientation. Figure 3 An exemplary image of a portion of an abrasive article including abrasive particles having randomly oriented abrasive particles.

[0032] It should be noted that while certain embodiments herein may have particles arranged in a random orientation, other embodiments may include particles arranged in a non-random or controlled distribution.

[0033] According to one embodiment, the abrasive particles 202 can cover the backing 201 in a first position having a first rotational orientation relative to a transverse axis 281 that defines the width of the backing 201 and is perpendicular to the longitudinal axis 280 that defines the intended grinding direction. Specifically, the abrasive particles 202 can have a rotational orientation defined by a first rotational angle between the transverse axis 284 that is perpendicular to the intended grinding direction and a size of the abrasive particle 202. Notably, the size referred to herein can refer to a bisector axis 231 of the abrasive particle 202 extending through a center point 221 of the abrasive particle 202 when viewed from top to bottom. Furthermore, the predetermined rotational orientation can be defined as a minimum angle 241 with the transverse axis 284 that extends through the center point 221. As Figure 2A As shown, the abrasive particles 202 can have a predetermined rotation angle, which is defined as the minimum angle 241 between the bisecting axis 231 and the transverse axis 281, wherein the transverse axis is parallel to the transverse axis 284. It should be understood that the transverse axis 281 can also be a radial axis, wherein the backing 201 has a circular or elliptical shape. According to embodiments, the angle 241 defining the rotational orientation of the abrasive particles 202 relative to the transverse axis 284 can be any value within a range of at least 0 degrees and not greater than 90 degrees.

[0034] like Figure 2AAs further shown, the abrasive grain 203 can be located at a second position overlying the backing 201 and having a rotational orientation. Notably, the rotational orientation of the abrasive grain 203 can be characterized as the minimum angle between a transverse axis 285 perpendicular to the grinding direction and a bisecting axis 232 of the abrasive grain 203 extending through the center point 222 of the abrasive grain 203. According to an embodiment, the rotation angle 208 can be any value in the range of at least 0 degrees to 90 degrees. Grains having an orientation facing the front have a rotation angle of 0 to 45 degrees, while grains having an orientation facing the side have a rotation angle of 45 to 90 degrees. In Figure 1A Exemplary particles in both face-on and side-on orientations can be found in .

[0035] Figure 2B The top view diagram of the part of the coated abrasive article of embodiment is included.As shown in the figure, abrasive article 200 may include a plurality of abrasive grains arranged at different positions on backing 201, wherein abrasive grain 253 limits the random distribution of particles on backing.In addition, abrasive grain 253 has random rotation orientation relative to each other, so that the rotation orientation of abrasive grain 253 changes grain by grain in a random manner.According to one aspect, the random rotation orientation of abrasive grain makes the rotation angle of an abrasive grain in one group can not be used to predict the rotation orientation of any next-door neighbor particle.Therefore, a group of abrasive grains with random rotation orientation does not have any short range (that is, next-door neighbor) or long range order about their rotation angle.Should be understood that any particle of backing that uses the system and process of this paper embodiment to be attached to can have random rotation orientation relative to each other.

[0036] At least a major part of the total content (weight or quantity) of the abrasive grains of the coated abrasive article of this paper embodiment can have random rotation orientation on the backing.In other cases, at least 10% or at least 20% or at least 30% or at least 40% or at least 50% or at least 60% or at least 70% or at least 80% or at least 90% or substantially all of the shaped abrasive grains in the total amount of the shaped abrasive grains have random rotation orientation.In one embodiment, all abrasive grains on the backing have random rotation orientation.

[0037] Figure 4A Includes a side view illustration of abrasive particles on a backing according to an embodiment. The methods disclosed in the embodiments herein can facilitate the formation of coated abrasive articles having a specific distribution and orientation of abrasive particles. Notably, without wishing to be bound by a particular theory, it is noted that the projection rate and efficiency of the process disclosed herein can facilitate improved control of the tilt angle of the abrasive particles adhered to the backing. To better understand these features, Figure 4AA side view illustration of three abrasive particles of different orientations is provided. It should be understood that, as described in more detail herein, the coated abrasive articles of the embodiments herein may have various contents of particles in the depicted orientations. The first particle 402 may have a particle axis 403 extending at a specific tilt angle 404 relative to the surface of the backing 401. The particle axis 403 may be parallel to the longitudinal axis of the first particle 402, which defines the length of the first particle 402. The first particle 402 represents a particle with an upright orientation having an tilt angle 404 in the range of greater than 65 degrees to 90 degrees. The second particle 411 may have a particle axis 412 extending at a specific tilt angle 413 relative to the surface of the backing 401. The particle axis 412 may be parallel to the longitudinal axis of the second particle 411, which defines the length of the second particle 411. The second particle 411 represents a particle with an oblique orientation having an tilt angle 413 in the range of greater than 5 degrees to 65 degrees. The third particles 421 may have a particle axis 422 extending at a particular tilt angle 423 relative to the surface of the backing 401. The particle axis 422 may be parallel to the longitudinal axis of the third particles 421, which defines the length of the third particles 421. The third particles 421 represent flat-oriented particles having a tilt angle 423 in the range of 0 degrees to not greater than 5 degrees (i.e., not greater than 5 degrees). Figure 4B A side view illustration of particles with a specific tilt angle on a backing according to an embodiment is included. As shown, particle 431 can be a shaped abrasive particle as described in the embodiments herein. Particle 431 can have a longitudinal axis 436 as defined later in this application. Backing 433 can define a substantially planar surface and have an axis 434 extending perpendicular to the substantially planar surface of backing 433. Tilt angle 435 is the minimum angle between the planar surface of backing 433 and an axis 432 extending parallel to the longitudinal axis 436 of particle 431. Certain particles can have longitudinal axes along various surfaces, which can result in different tilt angles. In such cases, the axis defining the maximum angle is the tilt angle.

[0038] Figure 4C include Figure 4B In some cases, a top-down view may provide a suitable vantage point for identifying the tilt direction and may therefore be suitable for measuring the tilt angle.

[0039] Figure 4DA side view illustration of particles with a specific tilt angle on a backing according to an embodiment is included. As shown, particles 441 may have a longitudinal axis 446 as defined later in this application. Particles 441 may be abrasive particles, and more specifically, may be non-shaped abrasive particles. Backing 443 may define a substantially planar surface and have an axis 444 extending perpendicular to the substantially planar surface of backing 443. Tilt angle 445 may be the minimum angle between axis 442 extending parallel to longitudinal axis 446 and the surface of backing 443. It should be understood that some particles (such as equiaxed particles) will not have a tilt angle.

[0040] Figure 4E include Figure 4D 445.

[0041] In one aspect, the coated abrasive article can include a plurality of abrasive particles wherein the tilt angle of the abrasive particles is controlled, which can contribute to improved performance of the coated abrasive. For example, at least a portion of the shaped abrasive particles have a tilt angle greater than 45 degrees. In other aspects, at least 10%, or at least 20%, or at least 30%, or at least 40%, or at least 50%, or at least 60%, or at least 70%, or at least 80%, or at least 90% of the total number of shaped abrasive particles, or substantially all of the shaped abrasive particles, have a tilt angle greater than 45 degrees.

[0042] In embodiments, the coated abrasive article may have a specific percentage of upright particles that can promote improved performance and / or manufacturing of the abrasive article. Upright particles can be defined as particles having an angle of inclination of 65 to 90 degrees. In embodiments, the upright abrasive particles can account for at least 10% of the total number of abrasive particles, or at least 20%, or at least 30%, or at least 40%, or at least 50%, or at least 55%, or at least 57%, or at least 60%, or at least 62%, or at least 65%, or at least 67%, or at least 70%, or at least 72%, or at least 75%, or at least 77%, or at least 80%, or at least 82%, or at least 85%, or at least 87%, or at least 90% of the total number of abrasive particles. In another embodiment, the upright abrasive particles may comprise no more than 99.9% of the total number of abrasive particles, or no more than 99%, or no more than 98%, or no more than 97%, or no more than 96%, or no more than 95% of the total number of abrasive particles. It should be understood that the percentage of upright particles may be between any of the above minimum and maximum values, including, for example, but not limited to, at least 20% and no more than 99%, or at least 50% and no more than 95%.

[0043] In embodiments, coated abrasive article can have the tilted particle that can promote the performance that improves abrasive article and / or the specific percentage of manufacturing.Tilted particle can be defined as the particle with the angle of inclination of 5 degree to 65 degree.In embodiments, tilted abrasive grain can account for at least 1% in the sum of abrasive grain, or at least 2% in the sum of abrasive grain, or at least 3% or at least 4% or at least 5% or at least 6% or at least 7% or at least 8% or at least 9% or at least 10% or at least 11% or at least 12% or at least 13% or at least 14% or at least 15% or at least 16% or at least 17% or at least 18% or at least 20% or at least 25%. In another embodiment, the tilted abrasive particles may comprise no more than 90% of the total number of abrasive particles, or no more than 85%, or no more than 80%, or no more than 75%, or no more than 70%, or no more than 65%, or no more than 60%, or no more than 55%, or no more than 50%, or no more than 45%, or no more than 40%, or no more than 35%, or no more than 30%, or no more than 25%, or no more than 20%, or no more than 18%, or no more than 15%, or no more than 12%, or no more than 10%. It should be understood that the percentage of tilted particles may be between any of the above minimum and maximum values, including, for example, but not limited to, at least 5% and no more than 80%, or at least 15% and no more than 35%.

[0044] In embodiments, coated abrasive article can have the good orientation particle of the specific percentage that can promote the performance and / or manufacture of improving abrasive article.Good orientation particle can be defined as the particle with the tilt angle of 5 degree to 90 degree, and comprises tilted particle and upright particle.In embodiments, good orientation abrasive grain can account for at least 60% in the sum of abrasive grain, or at least 62% in the sum of abrasive grain, or at least 65% or at least 67% or at least 70% or at least 72% or at least 75% or at least 77% or at least 80% or at least 82% or at least 85% or at least 87% or at least 90% or at least 92% or at least 95%.In another embodiment, good orientation abrasive grain can be not more than 99.9% or not more than 99% or not more than 98% or not more than 97% or not more than 96% or not more than 95% in the sum of abrasive grain. It will be appreciated that the percentage of well-oriented particles can be between any of the minimum and maximum values ​​noted above, including for example but not limited to at least 5% and not more than 80%, or at least 15% and not more than 35%.

[0045] In an embodiment, the coated abrasive article may have a specific percentage of fallen particles that can promote the improvement of the performance and / or manufacture of the abrasive article. Fallen particles can be defined as particles with an inclination angle of 0 to 5 degrees. In an embodiment, the fallen abrasive particles can account for at least 0.1% of the total number of abrasive particles, or at least 0.2%, or at least 0.4%, or at least 0.6%, or at least 0.8%, or at least 1%, or at least 1.5%, or at least 2%, or at least 2.5%, or at least 3%, or at least 3.5%, or at least 4%, or at least 4.5%, or at least 5%. In another embodiment, the fallen abrasive particles can account for no more than 20% of the total number of abrasive particles, or no more than 18%, or no more than 15%, or no more than 12%, or no more than 10%, or no more than 9%, or no more than 8%, or no more than 7%, or no more than 6%, or no more than 5%. It should be understood that the percentage of fallen particles can be between any of the minimum and maximum values ​​noted above, including, for example but not limited to, at least 0.2% and no more than 15%, or at least 1% and no more than 9%.

[0046] In an embodiment, the coated abrasive article may have a specific percentage of inverted particles that can promote the improvement of the performance and / or manufacture of the abrasive article. Inverted particles can be defined as particles with an inclination angle of 5 to 90 degrees and a tip, corner or point extending into the base glue and one or more planar surfaces (such as a base) relative to the tip on the other end of the abrasive particle. Particles that have a tip at only one end of their longitudinal axis and at least one planar surface at the opposite end of the longitudinal axis are inverted. Exemplary particle shapes that can be in inverted orientation include triangles, 3-PT (3-PT) stars, pentagons, and pyramids. Particles with planar surfaces at both ends of their longitudinal axis (e.g., rods or cylinders, rectangular prisms) and particles with points at both ends of their longitudinal axis (e.g., toothpick-shaped, rhombus, 4-point (4-PT) stars) cannot be in inverted orientation. Inverted particles are not upright, tilted, falling, or well-oriented. In an embodiment, the inverse abrasive particles constitute at least 0.1% of the total number of abrasive particles, or at least 0.2%, or at least 0.4%, or at least 0.6%, or at least 0.8%, or at least 1%, or at least 1.5%, or at least 2%, or at least 2.5%, or at least 3%, or at least 3.5%, or at least 4%, or at least 4.5%, or at least 5%. In another embodiment, the inverse abrasive particles may constitute no more than 20% of the total number of abrasive particles, or no more than 18%, or no more than 15%, or no more than 12%, or no more than 10%, or no more than 9%, or no more than 8%, or no more than 7%, or no more than 6%, or no more than 5% of the total number of abrasive particles. It should be understood that the percentage of inverse particles can be between any of the above minimum and maximum values, including, for example, but not limited to, at least 0.2% and no more than 15%, or at least 1% and no more than 9%.

[0047] In embodiments, the coated abrasive grains may have a specific ratio of upright particles (Pst) to inclined particles (Psl) (Pst / Psl) that may facilitate improved performance and / or manufacture of abrasive articles. In embodiments, Pst / Psl may be at least 1, or at least 1.2, or at least 1.4, or at least 1.6, or at least 1.8, or at least 2.0, or at least 2.2, or at least 2.4, or at least 2.6, or at least 2.8, or at least 3.0, or at least 3.2, or at least 3.4, or at least 3.6, or at least 3.8, or at least 4.0, or at least 4.2, or at least 4.4, or at least 4.6, or at least 4.8, or at least 5.0, or at least 5.2, or at least 5.4, or at least 5.6. In another embodiment, Pst / Psl may be no greater than 100, or no greater than 95, or no greater than 90, or no greater than 80, or no greater than 70, or no greater than 60, or no greater than 50, or no greater than 40, or no greater than 30, or no greater than 20, or no greater than 10. It should be understood that Pst / Psl can be between any of the above minimum and maximum values, including for example, but not limited to, at least 1.2 and no greater than 95, or at least 2.0 and no greater than 40.

[0048] In embodiments, the coated abrasive grains may have a specific ratio of standing particles (Pst) to falling particles (Pf) (Pst / Pf) that may facilitate improved performance and / or manufacture of abrasive articles. In embodiments, Pst / Pf may be at least 2.0, or at least 2.2, or at least 2.4, or at least 2.6, or at least 2.8, or at least 3.0, or at least 3.2, or at least 3.4, or at least 3.6, or at least 3.8, or at least 4.0, or at least 4.2, or at least 4.4, or at least 4.6, or at least 4.8, or at least 5.0, or at least 5.2, or at least 5.4, or at least 5.6, or at least 5.8, or at least 6.0, or at least 6.2, or at least 6.4, or at least 6.6, or at least 6.8, or at least 7.0, or at least 7.2, or at least 7.4, or at least 7.6, or at least 7.8, or at least 8.0. In another embodiment, Pst / Pf may be no greater than 1000, or no greater than 800, or no greater than 500, or no greater than 200, or no greater than 100, or no greater than 95. It should be understood that Pst / Pf can be between any of the above minimum and maximum values, including, for example, but not limited to, at least 2.0 and no greater than 500, or at least 2.6 and no greater than 95.

[0049] In embodiments, the coated abrasive grains may have a specific ratio of tilted particles (Psl) to fallen particles (Pf) (Psl / Pf) that can facilitate improved performance and / or manufacture of abrasive articles. In embodiments, Psl / Pf can be at least 1, or at least 1.2, or at least 1.4, or at least 1.6, or at least 1.8, or at least 2.0, or at least 2.2, or at least 2.4, or at least 2.6, or at least 2.8, or at least 3.0, or at least 3.2, or at least 3.4, or at least 3.6, or at least 3.8, or at least 4.0, or at least 4.2, or at least 4.4, or at least 4.6, or at least 4.8, or at least 5.0, or at least 5.2, or at least 5.4, or at least 5.6. In another embodiment, Psl / Pf may be no greater than 100, or no greater than 95, or no greater than 90, or no greater than 80, or no greater than 70, or no greater than 60, or no greater than 50, or no greater than 40, or no greater than 30, or no greater than 20, or no greater than 10, or no greater than 8, or no greater than 6. It should be understood that Psl / Pf can be between any of the above minimum and maximum values, including for example, but not limited to, at least 2.0 and no greater than 95, or at least 2.6 and no greater than 70.

[0050] In embodiments, the coated abrasive grains may have a specific ratio of upright particles (Pst) to inverted particles (Pi) (Pst / Pi) that may facilitate improved performance and / or manufacture of abrasive articles. In embodiments, Pst / Pi may be at least 1, or at least 2.0, or at least 3.0, or at least 4.0, or at least 5.0, or at least 6, or at least 7, or at least 8, or at least 9, or at least 10, or at least 12, or at least 15, or at least 18, or at least 20, or at least 25, or at least 30, or at least 40, or at least 50. In another embodiment, Pst / Pi may be no greater than 100, or no greater than 95, or no greater than 90, or no greater than 80, or no greater than 70, or no greater than 60, or no greater than 50, or no greater than 40, or no greater than 30, or no greater than 20, or no greater than 10, or no greater than 8, or no greater than 6. It should be understood that Pst / Pi can be between any of the above minimum and maximum values, including, for example but not limited to, at least 2.0 and no more than 80, or at least 6 and no more than 20.

[0051] In embodiments, the coated abrasive grains may have a specific ratio of inclined particles (Psl) to inverted particles (Pi) (Psl / Pi) that may facilitate improved performance and / or manufacture of abrasive articles. In embodiments, Psl / Pi may be at least 0.6, or at least 0.7, or at least 0.8, or at least 0.9, or at least 1, or at least 1.2, or at least 1.4, or at least 1.6, or at least 1.8, or at least 2.0, or at least 2.2, or at least 2.4, or at least 2.6, or at least 2.8, or at least 3.0, or at least 3.2, or at least 3.4, or at least 3.6, or at least 3.8, or at least 4.0, or at least 4.2, or at least 4.4, or at least 4.6, or at least 4.8, or at least 5.0, or at least 5.2, or at least 5.4, or at least 5.6. In another embodiment, Psl / Pi can be no greater than 100, or no greater than 95, or no greater than 90, or no greater than 80, or no greater than 70, or no greater than 60, or no greater than 50, or no greater than 40, or no greater than 30, or no greater than 20, or no greater than 10, or no greater than 8, or no greater than 6, or no greater than 4, or no greater than 3, or no greater than 2, or no greater than 1.5. It should be understood that Psl / Pi can be between any of the above minimum and maximum values, including, for example, but not limited to, at least 2.0 and no greater than 95, or at least 2.6 and no greater than 70.

[0052] In embodiments, the coated abrasive grains may have a specific ratio of falling particles (Pf) to inverted particles (Pi) (Pf / Pi) that may facilitate improved performance and / or manufacture of abrasive articles. In embodiments, Pf / Pi may be at least 0.6, or at least 0.7, or at least 0.8, or at least 0.9, or at least 1, or at least 1.2, or at least 1.4, or at least 1.6, or at least 1.8, or at least 2.0, or at least 2.2, or at least 2.4, or at least 2.6, or at least 2.8, or at least 3.0, or at least 3.2, or at least 3.4, or at least 3.6, or at least 3.8, or at least 4.0, or at least 4.2, or at least 4.4, or at least 4.6, or at least 4.8, or at least 5.0. In another embodiment, Pf / Pi may be no greater than 100, or no greater than 95, or no greater than 90, or no greater than 80, or no greater than 70, or no greater than 60, or no greater than 50, or no greater than 40, or no greater than 30, or no greater than 20, or no greater than 10, or no greater than 8, or no greater than 6, or no greater than 4, or no greater than 3, or no greater than 2, or no greater than 1.5. It should be understood that Pf / Pi may be between any of the above minimum and maximum values, including, for example, but not limited to, at least 2.0 and no greater than 95, or at least 2.6 and no greater than 70.

[0053] While the embodiments herein have referred to particles, these particles may include abrasive particles, secondary particles, or any combination thereof. Various types of abrasive particles and / or secondary particles can be used in the abrasive articles described in the embodiments herein. Figure 5A Figure 5 includes a perspective view of a shaped abrasive particle according to an embodiment. The shaped abrasive particle 500 may include a body 501 including a major surface 502, a major surface 503, and a side surface 504 extending between the major surface 502 and the major surface 503. Figure 5A As shown, the body 501 of the shaped abrasive particle 500 can be a thin shaped body in which the major surface 502 and the major surface 503 are larger than the side surface 504. In addition, the body 501 can include a longitudinal axis 510 extending from a point to the base and passing through a midpoint 550 on the major surface 502 or the major surface 503. The longitudinal axis 510 can define the longest dimension of the body along the major surface and passing through the midpoint 550 of the major surface 502.

[0054] In some particles, if the midpoint of the main surface of the body is not obvious, the main surface can be viewed from top to bottom, the closest circle can be drawn around the two-dimensional shape of the main surface, and the center of the circle can be used as the midpoint of the main surface. Figure 5B include Figure 5A 5. It is noteworthy that the body 501 includes a major surface 502 having a triangular two-dimensional shape. A circle 560 is drawn around the triangle to facilitate locating the midpoint 550 on the major surface 502.

[0055] Reference again Figure 5A , the body 501 may further include a transverse axis 511 defining the width of the body 501, the transverse axis extending substantially perpendicularly to the longitudinal axis 510 on the same major surface 502. Finally, as shown, the body 501 may include a vertical axis 512, which may define the height (or thickness) of the body 501 in the case of a thin shaped body. For a thin shaped body, the length of the longitudinal axis 510 is greater than the length of the vertical axis 512. As shown, the thickness 512 may extend between the major surface 502 and the major surface 503 along the side surface 504 and be perpendicular to the plane defined by the longitudinal axis 510 and the transverse axis 511. It should be understood that the length, width, and height of the abrasive particles mentioned herein may refer to the average value obtained from a suitable sampling size of abrasive particles of a larger group (including, for example, a group of abrasive particles fixed to a fixed abrasive).

[0056] Figure 5AIncluding the illustration of the shaped abrasive grains with a two-dimensional shape as defined by the plane of the upper main surface 502 or the main surface 503, the shaped abrasive grains have a roughly triangular two-dimensional shape. It should be understood that the shaped abrasive grains of the embodiments herein are not limited thereto and may include other two-dimensional shapes. For example, the shaped abrasive grains of the embodiments herein may include particles of a body with a two-dimensional shape, which is defined by the main surface of the body from the shape group including the following shapes: polygons, regular polygons, irregular polygons, irregular polygons including an arc or curved edge or a portion of an edge, ellipsoids, numbers, Greek alphabet characters, Latin alphabet characters, Russian alphabet characters, Japanese kanji characters, complex shapes with a combination of polygonal shapes, shapes (e.g., star-shaped) including a central area and a plurality of arms (e.g., at least three arms) extending from the central area, and combinations thereof. Specific polygonal shapes include rectangles, trapezoids, quadrilaterals, pentagons, hexagons, heptagons, octagons, nine angles, decagons, and any combination thereof. In another embodiment, the shaped abrasive particles can have a two-dimensional shape, such as an irregular trapezoid, an irregular pentagon, an irregular hexagon, an irregular heptagon, an irregular octagon, an irregular nonagon, an irregular decagon, and combinations thereof. An irregular polygonal shape is a shape in which at least one of the edges defining a polygonal shape is different in size (e.g., length) relative to another edge. As shown in other embodiments herein, the two-dimensional shape of some shaped abrasive particles can have a specific number of external points or external corners. For example, when viewed in a plane defined by the length and width, the body of the shaped abrasive particle can have a two-dimensional polygonal shape, wherein the body includes a two-dimensional shape having at least 4 external points (e.g., a quadrilateral), a two-dimensional shape having at least 5 external points (e.g., a pentagon), a two-dimensional shape having at least 6 external points (e.g., a hexagon), a two-dimensional shape having at least 7 external points (e.g., a heptagon), a two-dimensional shape having at least 8 external points (e.g., an octagon), a two-dimensional shape having at least 9 external points (e.g., a nonagon), etc.

[0057] Figure 7 700 includes a perspective view of a shaped abrasive particle according to another embodiment. Notably, the shaped abrasive particle 700 can include a body 701 including a surface 702 and a surface 703, which can be referred to as end faces 702 and 703. The body can also include major surfaces 704, 705, 706, 707 extending between and coupled to the end faces 702 and 703. Figure 7The shaped abrasive particles of are elongated shaped abrasive particles having a longitudinal axis 710 extending along the major surface 705 and passing through a midpoint 740 between the end face 702 and the end face 703. For particles having a recognizable two-dimensional shape, such as those in FIG. Figure 7 For shaped abrasive particles, the longitudinal axis is the dimension that will be readily understood to define the length of the body passing through the midpoint of the major surface. For example, in Figure 7 In FIG, the longitudinal axis 710 of the shaped abrasive particle 700 extends between the end face 702 and the end face 703 parallel to the edge defining the major surface as shown. Such a longitudinal axis is consistent with how the length of the rod will be defined. Notably, the longitudinal axis 710 does not extend diagonally between the corner connecting the end face 702 and the end face 703 and the edge defining the major surface 705, although such a line may define a maximum length dimension. In the case where the major surface has undulations or minor imperfections compared to a perfectly planar surface, a top-down two-dimensional image that ignores the undulations can be used to determine the longitudinal axis.

[0058] It should be understood that surface 705 is selected to illustrate longitudinal axis 710 because body 701 has a substantially square cross-sectional profile as defined by end face 702 and end face 703. Therefore, surfaces 704, 705, 706, and 707 can have approximately the same size relative to each other. However, in the case of other elongated abrasive particles, surface 702 and surface 703 can have different shapes, such as rectangular shapes, and therefore, at least one of surfaces 704, 705, 706, and 707 can be larger relative to the other surfaces. In such cases, the largest surface can define the major surface, and the longitudinal axis will extend along the largest of these surfaces through midpoint 740 and can extend parallel to the edges defining the major surface. As further shown, body 701 can include a transverse axis 711 extending perpendicular to longitudinal axis 710 within the same plane defined by surface 705. As further shown, the body 701 can also include a vertical axis 712 defining a height of the abrasive particles, wherein the vertical axis 712 extends in a direction perpendicular to a plane defined by the longitudinal axis 710 and the transverse axis 711 of the surface 705 .

[0059] It should be understood that similar to the thin shaped abrasive particles of FIG. 5 , Figure 7 The elongated shaped abrasive particles of FIG5 can have various two-dimensional shapes, such as those defined with respect to the shaped abrasive particles of FIG5. The two-dimensional shape of the body 701 can be defined by the shape of the end face 702 and the perimeter of the end face 703. The elongated shaped abrasive particles 700 can have any of the properties of the shaped abrasive particles of the embodiments herein.

[0060] Figure 8AA perspective view of a controlled height abrasive particle (CHAP) according to an embodiment is included. As shown, CHAP 800 may include a body 801 including a first major surface 802, a second major surface 803, and a side surface 804 extending between the first major surface 802 and the second major surface 803. Figure 8A As shown, the body 801 can have a thin, relatively planar shape, wherein the first major surface 802 and the second major surface 803 are larger than the side surface 804 and are substantially parallel to each other. In addition, the body 801 can include a longitudinal axis 810 extending through a midpoint 820 and defining the length of the body 801. The body 801 can also include a transverse axis 811 on the first major surface 802, which extends through the midpoint 820 of the first major surface 802, is perpendicular to the longitudinal axis 810, and defines the width of the body 801.

[0061] The body 801 may also include a vertical axis 812 that may define the height (or thickness) of the body 801. As shown, the vertical axis 812 may extend along the side surface 804 between the first major surface 802 and the second major surface 803 in a direction generally perpendicular to the plane defined by the axis 810 on the first major surface and the axis 811. For thin shaped bodies, such as Figure 8A As shown in the CHAP, the length may be equal to or greater than the width, and the length may be greater than the height. It should be understood that the length, width, and height of the abrasive particles referred to herein may refer to average values ​​obtained from a sample of a suitable size of abrasive particles from a batch of abrasive particles.

[0062] and Figure 5A 、 Figure 5B and Figure 7 The shaped abrasive particles are different. Figure 8A The CHAP does not have an easily identifiable two-dimensional shape based on the perimeter of the first major surface 802 or the second major surface 803. Such abrasive particles can be formed in a variety of ways, including but not limited to fracturing a thin layer of material to form abrasive particles having a major surface with a controlled height but with irregularly formed planes. For such particles, the longitudinal axis is defined as the longest dimension on the major surface extending through the midpoint on the surface. In the case where the major surface has undulations, a top-down two-dimensional image that ignores the undulations can be used to determine the longitudinal axis. In addition, as described above in Figure 5B As described in , the closest fitting circle can be used to identify the midpoint of the major surface and to identify the longitudinal and transverse axes.

[0063] Figure 8BIncluding illustrations of non-shaped particles, the non-shaped particles can be elongated, non-shaped abrasive particles or secondary particles, such as diluted fines, fillers, agglomerates, etc. Shaped abrasive particles can be formed by a specific process, including molding, printing, casting, extrusion, etc. Shaped abrasive particles can be formed so that each particle has the substantially identical surface and edge arrangement relative to each other. For example, a group of shaped abrasive particles generally have the same arrangement and orientation and / or two-dimensional shape relative to each other's surface and edge. Therefore, the shaped abrasive particles have relatively high shape fidelity and consistency in terms of the arrangement of the surface and edge relative to each other. In addition, constant height abrasive particles (CHAP) can also be formed by a specific process, which promotes the formation of thin shaped bodies, which can have irregular two-dimensional shapes when observing the main surface from top to bottom. CHAP can have a shape fidelity smaller than shaped abrasive particles, but can have a substantially plane and parallel main surface separated by a side surface.

[0064] In contrast, non-shaped particles can be formed by different processes and have different shape properties than shaped abrasive particles and CHAPs. For example, non-shaped particles are typically formed by a comminution process in which a block of material is formed that is then crushed and sieved to obtain abrasive particles of a specific size. However, non-shaped particles will have a generally random arrangement of surfaces and edges and will generally lack any recognizable two-dimensional or three-dimensional shape in the arrangement of surfaces and edges. Furthermore, non-shaped particles do not necessarily have shapes that are consistent with one another and therefore have significantly lower shape fidelity than shaped abrasive particles or CHAPs. Non-shaped particles are generally defined by the random arrangement of the surfaces and edges of each particle relative to other non-shaped particles.

[0065] Figure 8B A perspective view illustration of a non-formed particle is included. The non-formed particle 850 may have a body 851 that includes a generally random arrangement of edges 855 extending along the outer surface of the body 851. The body may also include a longitudinal axis 852 that defines the longest dimension of the particle. When viewed in two dimensions, the longitudinal axis 852 defines the longest dimension of the body. Thus, unlike shaped abrasive particles and CHAPs, which have longitudinal axes measured at a major surface, the longitudinal axes of non-formed particles are defined by the points on the body that are farthest from each other when the particle is viewed in two dimensions using an image or vantage point that provides a view of the longest dimension of the particle. That is, a particle such as Figure 8BThe elongated particles shown but non-shaped particles should be observed with a visual angle that makes the longest dimension obvious, to correctly evaluate the longitudinal axis. Body 851 may also include a transverse axis 853 that extends perpendicular to the longitudinal axis 852 and limits particle width. Transverse axis 853 may extend through the midpoint 856 of the longitudinal axis perpendicular to the longitudinal axis 852 in the same plane for identifying the longitudinal axis 852. Abrasive particles may have a height (or thickness) limited by a vertical axis 854. Vertical axis 854 may extend through midpoint 856, but direction is perpendicular to the plane for limiting longitudinal axis 852 and transverse axis 853. In order to evaluate height, it may be necessary to change the visual angle of the abrasive particles to observe the particles from a vantage point different from the vantage point for evaluating length and width.

[0066] In an embodiment, the plurality of abrasive particles 102 and 103 of the coated abrasive article may include shaped abrasive particles. In an embodiment, the shaped abrasive particles may be 3-PT star-shaped abrasive particles. The abrasive particles may have a length (l), a width (w), and a thickness (t), wherein width ≥ thickness and length ≥ thickness. The particles may have a primary aspect ratio based on the length of the body: width. The particles may have a secondary aspect ratio based on the length of the body: thickness. The particles may also have a tertiary aspect ratio based on the width of the body: thickness. The particles 102 and 103 may be elongated abrasive particles having a primary aspect ratio greater than 1.1:1.

[0067] In an embodiment, when observed in a plane of the length and width of the main body, a plurality of shaped abrasive particles may comprise a plurality of shaped abrasive particles with a 3-PT star-shaped two-dimensional shape. The main body may comprise at least 3 external angles and at least 4 side surface sections or at least 5 side surface sections or at least 6 side surface sections. In an embodiment, a plurality of shaped abrasive particles may comprise a main body with at least 3 external angles, wherein the sum of the angles of the external angles is less than 180 degrees. In an embodiment, a plurality of shaped abrasive particles may comprise a main body with at least 3 external angles, wherein each external angle in the external angles defines an angle that is less than 60 degrees, or less than 59 degrees, or less than 58 degrees, or less than 57 degrees, or less than 56 degrees, or less than 55 degrees. In an embodiment, a plurality of shaped abrasive particles may comprise a main body with at least 3 external angles and at least 3 internal angles, wherein the internal angle angle value of each internal angle in the internal angles is greater than any one of the external angle values ​​of any one of the at least 3 external angles.

[0068] An outside corner can be identified using the "rubber band test." If a rubber band is stretched around the body of the abrasive particle, the corner that contacts the rubber band and causes it to deflect will be an outside corner.

[0069] Figure 6AIncluded are top view images of 3-PT star-shaped abrasive particles according to particular embodiments. As shown, the shaped abrasive particle 600 can define a star-shaped body when viewed in two dimensions. Specifically, the shaped abrasive particle 600 can include a body 601 having a center portion 602 and a first arm 603, a second arm 604, and a third arm 605 extending from the center portion 602. The body 601 can have a length (l) measured as the longest dimension along a side of the particle and a width (w) measured as the longest dimension of the particle between a midpoint 653 of a side passing through a midpoint 690 of the body 601 and a first tip 606 of the first arm 603. The width can extend in a direction perpendicular to the length dimension. The body 601 can have a thickness (t) extending in a direction perpendicular to an upper or first major surface 610 of the body 601, thereby defining a third side surface 656 between the upper or first major surface 610 and the base surface 611, as shown in FIG. Figure 6B As shown, the figure is Figure 6A A side view illustration of an image of a particle.

[0070] The shaped abrasive particle 600 can have a body 601 in the form of a 3-PT star, defined by a first arm 603, a second arm 604, and a third arm 605 extending from a central portion 602. According to one particular embodiment, at least one of the arms (including, for example, the first arm 603) can have a midpoint width 613 that is less than a central portion width 612. The central portion 602 can be defined as the area between a midpoint 651 of a first side surface 654, a midpoint 652 of a second side surface 655, and a midpoint 653 of a third side surface 656, respectively. The central portion width 612 of the first arm 603 can be the width of the dimension between the midpoint 651 and the midpoint 652. The midpoint width 613 can be the width of a line along the first axis 660 at the midpoint between the central portion width 612 and the tip 606 of the first arm 603. In some cases, the midpoint width 613 can be no more than about 90% of the center portion width 612, such as no more than about 80%, no more than about 70%, no more than about 5%, or even no more than about 60%. Additionally, the midpoint width 613 can be at least about 10% of the center portion width 612, such as at least about 20%, at least about 30%, or even at least about 40%. It should be understood that the width of the midpoint width 613 relative to the center portion width 612 can be within a range between any of the above minimum and maximum percentages.

[0071] In addition, the body 601 may have at least one arm, such as the first arm 603, having a tip width at the tip 606 of the first arm 603 that is less than the midpoint width 613. In such cases where the tip 606 is sharply formed, the tip width can be considered to be zero. In the case where the tip 606 has a radius of curvature, the tip width can be considered to be the diameter of the circle defined by the radius of curvature. According to one embodiment, the tip width 614 may be no more than about 90% of the midpoint width 613, such as no more than about 80%, no more than about 70%, no more than about 60%, no more than about 50%, no more than about 40%, no more than about 30%, no more than about 20%, or even no more than about 10%. Furthermore, in certain non-limiting embodiments, the tip width 614 may be at least about 1% of the midpoint width 613, such as at least about 2%, at least about 3%, at least about 5%, or even at least about 10%. It will be appreciated that the width of the tip width 614 relative to the midpoint width 613 can be within a range between any of the minimum and maximum percentages noted above.

[0072] As further shown, the body 601 may have a first arm 603 including a first tip 606 that defines a first tip angle 621 between a first side surface 654 and a second side surface 655. According to an embodiment, the first tip angle may be less than about 60 degrees, such as not more than about 55 degrees, not more than about 50 degrees, not more than about 45 degrees, or even not more than about 40 degrees. In addition, the first tip angle may be at least about 5 degrees, such as at least about 8 degrees, at least about 10 degrees, at least about 15 degrees, at least about 20 degrees, at least about 25 degrees, or even at least about 30 degrees. The first tip angle may be within a range between any of the above minimum and maximum values.

[0073] The body 601 may include a second arm 604 having a second tip 607 that defines a second tip angle 622 between the second side surface 655 and the third side surface 656. The second tip angle may be substantially the same as the first tip angle, such as within 5% of the angle value. Alternatively, the second tip angle may be substantially different relative to the first tip angle.

[0074] The body 601 may include a third arm 605 having a third tip 608 that defines a third tip angle 623 between the first side surface 654 and the third side surface 656. The third tip angle may be substantially the same as the first tip angle or the second tip angle, such as within 5% of the angle value. Alternatively, the third tip angle may be substantially different relative to the first tip angle or the second tip angle.

[0075] Main body 601 can have total angle, and this total angle is the summation of the value of the first tip angle, the second tip angle and the third tip angle, and this total angle can be less than about 180 degree.In other embodiments, total angle can be not more than about 175 degree, such as not more than about 170 degree, not more than about 15 degree, not more than about 150 degree, such as not more than about 140 degree, not more than about 130 degree, not more than about 125 degree or even not more than about 120 degree.In addition, in a non-limiting embodiment, main body 601 can have at least about 60 degree, such as at least about 70 degree, at least about 80 degree, at least about 90 degree, such as at least about 95 degree, at least about 100 degree or even at least about 105 degree total angle.Should be understood that the sum angle can be in the scope between any one of above-mentioned minimum and maximum value.

[0076] As described herein, the body 601 can have a first side surface 654 extending between the first arm 606 and the third arm 608. In some cases, the first side surface 654 can have a curved profile.

[0077] Reference again Figure 6A , the body 601 may have a first side surface 654 having a first side segment 658 and a second side segment 659. The first side segment 658 may extend between the first tip 606 and the midpoint 651, and the second side segment 659 may extend between the third tip 608 and the midpoint 651. The first side segment 658 and the second side segment 659 may define an internal angle 662, which may be an obtuse angle. For example, the internal angle 662 may be greater than approximately 90 degrees, such as greater than approximately 95 degrees, greater than approximately 100 degrees, greater than approximately 110 degrees, or even greater than approximately 120 degrees. Furthermore, in one non-limiting embodiment, the internal angle 662 may be no greater than approximately 320 degrees, such as no greater than approximately 300 degrees, or even no greater than approximately 270 degrees. It should be understood that the internal angle may be within a range between any of the above minimum and maximum values.

[0078] The first side segment 658 can extend a substantial portion of the length of the first side surface 654. For example, the first side segment 658 can extend at least about 20% of the total length of the first side surface 654, such as at least about 25%, at least about 30%, at least about 35%, or even at least about 40%. Furthermore, in one non-limiting embodiment, the first side segment 658 can have a length (ls1) between the midpoint 651 and the first tip 606 that is no greater than about 80% of the total length of the side surface 654, such as no greater than about 75%, no greater than about 70%, or even no greater than about 5%. It should be understood that the length of the first side segment 658 can be within a range between any of the minimum and maximum percentages noted above.

[0079] The second side segment 659 can extend a substantial portion of the length of the first side surface 654. For example, the second side segment 659 can extend at least about 20% of the total length of the first side surface 654, such as at least about 25%, at least about 30%, at least about 35%, or even at least about 40%. Furthermore, in one non-limiting embodiment, the second side segment 659 can have a length (ls2) between the midpoint 651 and the third tip 608 that is no greater than about 80% of the total length of the side surface 654 (as a straight line between the first tip 606 and the third tip 608), such as no greater than about 75%, no greater than about 70%, or even no greater than about 5%. It should be understood that the length of the second side segment 659 can be within a range between any of the minimum and maximum percentages noted above.

[0080] Body 601 can include a first average side surface angle 631 between side surfaces 654, 655, and 656 and upper or first major surface 610. Body can also include a second side surface angle 632 between side surfaces 654, 655, and 656 and second major or base surface 612.

[0081] In embodiments, the abrasive grains may include a specific first side surface angle that can facilitate improved performance and / or manufacture of the abrasive grains. In embodiments, the first side surface angle can be in a range of at least 70 degrees and not more than 94 degrees, or in a range of at least 80 degrees and not more than 93 degrees, or in a range of at least 83 degrees and not more than 92 degrees, or in a range of at least 85 degrees and not more than 91 degrees.

[0082] In embodiments, the abrasive grains may include a specific second side surface angle that can promote improved performance and / or manufacture of the abrasive grains. In embodiments, the second side surface angle can be in the range of at least 70 degrees and not more than 94 degrees, or in the range of at least 80 degrees and not more than 93 degrees, or in the range of at least 83 degrees and not more than 92 degrees, or in the range of at least 85 degrees and not more than 91 degrees.

[0083] While the aforementioned body 601 of a 3-PT star shape has been illustrated as having an upper surface 610 having a two-dimensional shape that, as viewed in a plane of the length and width of the body, is substantially identical to the two-dimensional shape of the base surface or second major surface 611 of the body 601, other shapes are also contemplated. For example, in one embodiment, the cross-sectional shape of the body at the base surface may define a base surface shape selected from the group consisting of: a 3-PT star shape, a 4-PT star shape, a cross, a polygon, an ellipsoid, a number, a Greek alphabet character, a Latin alphabet character, a Russian alphabet character, a complex shape having a combination of polygonal shapes, and combinations thereof. Additionally, the cross-sectional shape of the body at the upper surface may define an upper surface shape that is different from the base surface shape and is selected from the group consisting of: a 3-PT star shape, a 4-PT star shape, a cross, a polygon, an ellipsoid, a number, a Greek alphabet character, a Latin alphabet character, a Russian alphabet character, a complex shape having a combination of polygonal shapes, and combinations thereof.

[0084] In particular cases, the upper surface shape may have an arcuate form of the base surface shape. For example, the upper surface shape may define an arcuate 3-PT two-dimensional shape, wherein the arcuate 3-PT two-dimensional shape defines arms having rounded ends. Specifically, the arms defined at the base surface may have a smaller radius of curvature at the tip than the corresponding radius of curvature at the upper surface.

[0085] As described in other embodiments herein, it should be understood that at least one of the arms of the body 601 can be formed with a twist such that the arm twists about a central axis. For example, the first arm 603 can twist about the axis 660. Furthermore, the body 601 can be formed such that at least one arm extends from a central region in an arcuate path.

[0086] In embodiments, the plurality of shaped abrasive particles may define a first group of abrasive particles. In embodiments, the first group of abrasive particles may include at least two different types of shaped abrasive particles, wherein the two different types of shaped abrasive particles differ from each other based on at least one property selected from the group consisting of particle size, two-dimensional shape, three-dimensional shape, composition, hardness, toughness, friability, density, particle size, state of agglomeration, lateral position, longitudinal position, rotational orientation, or any combination thereof.

[0087] In embodiments, abrasive article can comprise a second group of abrasive grains that is different from the first group of abrasive grains.The second group of abrasive grains can be different from the first group of abrasive grains based on at least one characteristic selected from the group consisting of particle diameter, two-dimensional shape, three-dimensional shape, composition, hardness, toughness, friability, density, particle size, agglomeration state, lateral position, longitudinal position, rotational orientation or any combination thereof.In other embodiments, the second group of abrasive grains comprises the dilution abrasive grain.In another embodiment, the second group of particles can comprise randomly shaped or non-shaped abrasive grains.

[0088] Shaped abrasive particles can be formed by a specific process, including molding, printing, casting, extrusion, etc. Shaped abrasive particles can be formed so that each particle has a substantially identical surface and edge arrangement relative to each other. For example, a group of shaped abrasive particles generally have the same arrangement and orientation and / or two-dimensional shape relative to each other's surface and edge. Therefore, shaped abrasive particles have relatively high shape fidelity and consistency in terms of the arrangement of surfaces and edges relative to each other. In contrast, compared with shaped abrasive particles, non-shaped particles can be formed by different processes and have different shape attributes. For example, non-shaped particles are generally formed by a comminution process, in which a material block is formed, which is then crushed and sieved to obtain abrasive particles of a specific size. However, non-shaped particles will have a roughly random arrangement of surfaces and edges, and will generally lack any identifiable two-dimensional or three-dimensional shape in the arrangement of surfaces and edges. In addition, non-shaped particles do not necessarily have shapes that are consistent with each other, and therefore have significantly lower shape fidelity than shaped abrasive particles. Non-shaped particles are generally defined by the random arrangement of the surfaces and edges of each particle relative to other non-shaped particles.

[0089] In embodiments, the abrasive article may include a specific percentage of cracked abrasive particles that can promote improved performance or manufacture of the abrasive article. As defined herein, cracks in a plurality of shaped abrasive particles include cracks that are visible after magnification (such that the width of the particle is equal to 50% to 95% of the field of view). In embodiments, the abrasive article may include a plurality of shaped abrasive particles having at least 3 internal angles, wherein no more than 50%, or no more than 45%, or no more than 40%, or no more than 35%, or no more than 30%, or no more than 25%, or no more than 20%, or no more than 18%, or no more than 16%, or no more than 14%, or no more than 12%, or no more than 10%, or no more than 9%, or no more than 8%, or no more than 7%, or no more than 6%, or no more than 5%, or no more than 4%, or no more than 3%, or no more than 2%, or no more than 1% of the total number of shaped abrasive particles have cracks at the internal angles on the first major surface. In an embodiment, the abrasive article may include a plurality of shaped abrasive particles having at least 3 interior corners, wherein no more than 50%, or no more than 45%, or no more than 40%, or no more than 35%, or no more than 30%, or no more than 25%, or no more than 20%, or no more than 18%, or no more than 16%, or no more than 14%, or no more than 12%, or no more than 10%, or no more than 9%, or no more than 8%, or no more than 7%, or no more than 6%, or no more than 5%, or no more than 4%, or no more than 3%, or no more than 2%, or no more than 1% of the total number of the shaped abrasive particles have cracks at the interior corners on the first major surface. In an embodiment, the abrasive article may include a plurality of shaped abrasive particles having a body having at least 3 internal corners, and wherein at least 0.01%, or at least 0.5%, or at least 1%, or at least 2%, or at least 3%, or at least 4%, or at least 5%, or at least 8%, or at least 10% of the total number of shaped abrasive particles have cracks at the internal corners on the first major surface. In an embodiment, the abrasive article may include a plurality of shaped abrasive particles having a body having at least 3 internal corners, and wherein at least 0.01%, or at least 0.5%, or at least 1%, or at least 2%, or at least 3%, or at least 4%, or at least 5%, or at least 8%, or at least 10% of the total number of shaped abrasive particles have cracks at the internal corners on the second major surface. It should be understood that the percentage of the plurality of shaped abrasive particles having cracks at the internal corners can be between any of the above minimum and maximum values, including, for example, but not limited to, at least 0.5% and not more than 50%, or at least 5% and not more than 30%.

[0090] In an embodiment, an abrasive article may include a plurality of shaped abrasive particles of a specific material that may facilitate improved manufacture and / or performance of the abrasive article. In an embodiment, an abrasive article may include a plurality of shaped abrasive particles comprising a ceramic material. In an embodiment, an abrasive article may include a plurality of shaped abrasive particles comprising at least one of a nitride, an oxide, a carbide, a boride, an oxynitride, an oxyboride, a diamond, a carbonaceous material, or any combination thereof. In an embodiment, an abrasive article may include a plurality of shaped abrasive particles comprising an oxide compound or composite, such as aluminum oxide, zirconium oxide, titanium oxide, yttrium oxide, chromium oxide, strontium oxide, silicon oxide, magnesium oxide, a rare earth oxide, or any combination thereof.

[0091] In an embodiment, an abrasive article may include an abrasive grain having at least one fracture feature. When the abrasive grain is in a front-facing orientation relative to the grinding direction, the fracture feature may promote fracture, while when the abrasive grain is in a side-facing orientation relative to the grinding direction, the fracture feature does not promote fracture. In an embodiment, the fracture feature may be located on the first major surface of the abrasive grain. In a more specific embodiment, the abrasive grain may include a fracture feature on at least the first major surface and a fracture feature on at least the second major surface. In an alternative embodiment, the fracture feature may be on the side surface. In another embodiment, at least 2 side surfaces of the abrasive grain may include a fracture feature. In an embodiment, the fracture feature may be continuous. In an alternative embodiment, the fracture feature may be discontinuous. In an embodiment, the fracture feature may be a semicircular indentation in the surface of the abrasive grain.

[0092] Abrasive grain can have the fracture characteristic portion with specific depth, and it can promote the performance and / or the manufacturing of improving abrasive article.In embodiments, abrasive grain can comprise that the degree of depth is at least 5 microns or at least 6 microns or at least 7 microns or at least 8 microns or at least 9 microns or at least 10 microns or at least 11 microns or at least 12 microns or at least 13 microns or at least 14 microns or at least 15 microns fracture characteristic portion.In one embodiment, abrasive grain can comprise that the degree of depth is not more than 80 microns or is not more than 75 microns or is not more than 70 microns or is not more than 65 microns or is not more than 60 microns or is not more than 55 microns or is not more than 50 microns or is not more than 45 microns or is not more than 40 microns or is not more than 35 microns or is not more than 30 microns or is not more than 25 microns or is not more than 20 microns or is not more than 15 microns fracture characteristic portion. It should be understood that the depth of the fracture feature can be between any of the minimum and maximum values ​​noted above, including, for example but not limited to, at least 6 microns and no greater than 75 microns, or at least 10 microns and no greater than 20 microns.

[0093] Abrasive grains can have fracture features at a certain height relative to the total height H of the abrasive grains, which can contribute to improved performance and / or manufacture of abrasive articles. In embodiments, abrasive grains can include fracture features at a height of at least 55% H, or at least 56% H, or at least 57% H, or at least 58% H, or at least 59% H, or at least 60% H, or at least 61% H, or at least 62% H, or at least 63% H, or at least 64% H, or at least 65% H, or at least 66% H, or at least 67% H, or at least 68% H, or at least 69% H, or at least 70% H, or at least 71% H, or at least 72% H, or at least 73% H, or at least 74% H, or at least 75% H. In an embodiment, the abrasive grains may include fracture features at a height of less than 90% H, or less than 89% H, or less than 88% H, or less than 87% H, or less than 86% H, or less than 85% H, or less than 84% H, or less than 83% H, or less than 82% H, or less than 81% H, or less than 80% H, or less than 79% H, or less than 78% H, or less than 77% H, or less than 76%. It should be understood that the height of the fracture feature can be between any of the above minimum and maximum values, including, for example, but not limited to, at least 55% H and no more than 90% H, or at least 62% H and no more than 87% H.

[0094] In an embodiment, abrasive grain can have a fracture feature portion with a specific radius of curvature, and this fracture feature portion can promote the performance and / or manufacture of improving abrasive article.The radius of curvature can be determined by superimposing a best fit circle on the curvature of the fracture feature portion and determining the radius of the best fit circle.Any suitable computer program (such as ImageJ) can be used in combination with the image (for example, SEM image or optical microscope image) of the suitable magnification of abrasive grain, to measure the best fit circle accurately.In an embodiment, abrasive grain can have a fracture feature portion, and this fracture feature portion has at least 100 microns, or at least 110 microns, or at least 120 microns, or at least 130 microns, or at least 140 microns, or at least 150 microns, or at least 160 microns, or at least 170 microns, or at least 180 microns, or at least 190 microns, or at least 200 microns, or at least 210 microns, or at least 220 microns, or at least 230 microns, or at least 240 microns, or at least 250 microns, or at least 260 microns, or at least 270 microns, or at least 280 microns or at least 450 micrometers, or at least 460 micrometers, or at least 470 micrometers, or at least 480 micrometers, or at least 490 micrometers, or at least 500 micrometers, or at least 510 micrometers, or at least 520 micrometers, or at least 530 micrometers, or at least 540 micrometers, or at least 550 micrometers, or at least 560 micrometers, or at least 570 micrometers, or at least 580 micrometers, or at least 590 micrometers, or at least 600 micrometers, or at least 610 micrometers, or at least 620 micrometers, or at least 630 micrometers, or at least 640 micrometers, or at least 650 micrometers, or at least 660 micrometers, or at least 670 micrometers, or at least 680 micrometers. In yet other embodiments, the abrasive grains can have a fracture feature having a radius of curvature of no greater than 3000 microns, or no greater than 2500 microns, or no greater than 2000 microns, or no greater than 1900 microns, or no greater than 1800 microns, or no greater than 1700 microns, or no greater than 1600 microns, or no greater than 1500 microns, or no greater than 1400 microns, or no greater than 1300 microns, or no greater than 1200 microns, or no greater than 1100 microns, or no greater than 1000 microns, or no greater than 900 microns, or no greater than 800 microns, or no greater than 700 microns, or no greater than 600 microns, or no greater than 500 microns. It should be understood that the radius of curvature of the fracture feature can be between any of the above minimum and maximum values, including, for example, but not limited to, at least 100 microns and no greater than 3000 microns, or at least 400 microns and no greater than 500 microns. In still other embodiments, it will be appreciated that the fracture features of the abrasive particles can be straight lines without a radius of curvature.

[0095] In an embodiment, the abrasive grains may have a fracture feature defined by a semicircular indentation having a specific radius of curvature of the indentation that may facilitate improved performance and / or manufacture of the abrasive article. The radius of curvature of the indentation may be determined by superimposing a best fit circle onto the curvature of the fracture feature indentation and determining the radius of the best fit circle. Any suitable computer program (such as ImageJ) may be used in conjunction with an image (e.g., an SEM image or an optical microscope image) of a suitable magnification of the abrasive grains to accurately measure the best fit circle. For example, Figure 9 In one embodiment, abrasive grain can have a fracture characteristic portion, and this fracture characteristic portion has at least 5 microns, at least 10 microns, at least 15 microns, or at least 20 microns, or at least 25 microns, or at least 30 microns, or at least 35 microns, or at least 40 microns, or at least 45 microns, or at least 50 microns of indentation curvature radius. In other embodiments, abrasive grain can have a fracture characteristic portion, and this fracture characteristic portion has not more than 100 microns, or not more than 90 microns, or not more than 80 microns, or not more than 70 microns, or not more than 60 microns, or not more than 50 microns, or not more than 40 microns, or not more than 30 microns, or not more than 20 microns of indentation curvature radius.Should be understood that the indentation curvature radius of the fracture characteristic portion can be between any one in above-mentioned minimum and maximum value, comprise such as but not limited to at least 5 microns and be not more than 100 microns, or at least 10 microns and be not more than 20 microns.

[0096] In certain embodiments, the abrasive particles may have a 3-PT star-shaped two-dimensional shape when viewed in the plane of the length and width of the body. For example, Figure 10 A perspective view of a 3-PT star-shaped abrasive particle 1000 having a fracture feature as described herein. The shaped abrasive particle 1000 may include a body 1010 having a central portion 1012 and a first arm 1013, a second arm 1014, and a third arm 1015 extending from the central portion 1012. In an embodiment, each of the arms 1013, 1014, 1015 may include a fracture feature 1020 having a semicircular indentation. In an embodiment, the fracture feature 1020 of each of the arms 1013, 1014, 1015 may have the same radius of curvature. In yet another embodiment, the fracture feature 1020 of each of the arms 1013, 1014, 1015 may have a different radius of curvature.

[0097] Many different aspects and embodiments are possible. Some of those aspects and embodiments are described herein. After reading this specification, the skilled person will appreciate that those aspects and embodiments are merely exemplary and do not limit the scope of the invention. Embodiment can be according to any one or more embodiments in the embodiments listed below.

[0098] Implementation Plan

[0099] Embodiment 1. An abrasive particle, comprising:

[0100] a first major surface,

[0101] the second major surface,

[0102] a side surface between the first main surface and the second main surface,

[0103] Total height H,

[0104] and at least one fracture feature located at a height of 55%H to 90%H.

[0105] Embodiment 2. The abrasive particle of embodiment 1, wherein the at least one fracture feature is located on the first major surface.

[0106] Embodiment 3. The abrasive particle of Embodiment 1, wherein the abrasive particle comprises at least one fracture feature on the first major surface and at least one fracture feature on the second major surface.

[0107] Embodiment 4. The abrasive particle of embodiment 1, wherein the at least one fracture feature is on a side surface.

[0108] Embodiment 5. The abrasive particle of embodiment 1, wherein at least two fracture features are located on different side surfaces.

[0109] Embodiment 6. The abrasive grain of embodiment 1, wherein the fracture feature is located at a height of at least 56% H, or at least 57% H, or at least 58% H, or at least 59% H, or at least 60% H, or at least 61% H, or at least 62% H, or at least 63% H, or at least 64% H, or at least 65% H, or at least 66% H, or at least 67% H, or at least 68% H, or at least 69% H, or at least 70% H, or at least 71% H, or at least 72% H, or at least 73% H, or at least 74% H, or at least 75% H.

[0110] Embodiment 7. An abrasive grain according to embodiment 1, wherein the fracture feature is located at a height of less than 89% H, or less than 88% H, or less than 87% H, or less than 86% H, or less than 85% H, or less than 84% H, or less than 83% H, or less than 82% H, or less than 81% H, or less than 80% H, or less than 79% H, or less than 78% H, or less than 77% H, or less than 76% H.

[0111] Embodiment 8. The abrasive particle of Embodiment 1, wherein the fracture feature is a semicircular indentation in the surface of the abrasive particle.

[0112] Embodiment 9. The abrasive particle of embodiment 8, wherein the fracture feature is discontinuous.

[0113] Embodiment 10. The abrasive particle of Embodiment 8, wherein the fracture feature is continuous.

[0114] Embodiment 11. The abrasive grain of Embodiment 1, wherein the fracture features have a depth of at least 5 microns, or at least 6 microns, or at least 7 microns, or at least 8 microns, or at least 9 microns, or at least 10 microns, or at least 11 microns, or at least 12 microns, or at least 13 microns, or at least 14 microns, or at least 15 microns.

[0115] Embodiment 12. The abrasive grain of Embodiment 1, wherein the fracture features have a depth of not greater than 80 microns, or not greater than 75 microns, or not greater than 70 microns, or not greater than 65 microns, or not greater than 60 microns, or not greater than 55 microns, or not greater than 50 microns, or not greater than 45 microns, or not greater than 40 microns, or not greater than 35 microns, or not greater than 30 microns, or not greater than 25 microns, or not greater than 20 microns, or not greater than 15 microns.

[0116] Embodiment 13. The abrasive particles of Embodiment 1, wherein the abrasive is a shaped particle or an elongated particle having a length (l), a width (w), and a thickness (t), wherein the width > the thickness, and the length > the thickness.

[0117] Embodiment 14. The abrasive particle of embodiment 1, wherein the abrasive particle has a 3-PT star-shaped two-dimensional shape when viewed in the plane of the length and width of the body.

[0118] Embodiment 15. The abrasive particle of embodiment 1, further comprising at least 3 exterior corners, and wherein the side surface comprises at least 4 side surface segments, or at least 5 side surface segments, or at least 6 side surface segments.

[0119] Embodiment 16. The abrasive grain of Embodiment 1, further comprising an average side surface angle between the side surface and the first major surface, the average side surface angle being at least 70 degrees and not greater than 94 degrees, or within a range of at least 80 degrees and not greater than 93 degrees, or within a range of at least 83 degrees and not greater than 92 degrees, or within a range of at least 85 degrees and not greater than 91 degrees.

[0120] Embodiment 17. The abrasive grain of Embodiment 1, further comprising an average side surface angle between the side surface and the second major surface, the average side surface angle being at least 70 degrees and not greater than 94 degrees, or within a range of at least 80 degrees and not greater than 93 degrees, or within a range of at least 83 degrees and not greater than 92 degrees, or within a range of at least 85 degrees and not greater than 91 degrees.

[0121] Embodiment 18. The abrasive particle of Embodiment 1, further comprising a body having at least three external angles, wherein the sum of the angles of the external angles is less than 180 degrees.

[0122] Embodiment 19. The abrasive grain of Embodiment 1, further comprising at least three external angles, wherein each of the external angles defines an angle of less than 60 degrees, or less than 59 degrees, or less than 58 degrees, or less than 57 degrees, or less than 56 degrees, or less than 55 degrees.

[0123] Embodiment 20. The abrasive grain of Embodiment 1, further comprising at least three exterior angles and at least three interior angles, wherein each of the interior angles has an interior angle value greater than any of the exterior angle values ​​of any of the at least three exterior angles.

[0124] Embodiment 21. The abrasive grain of embodiment 1, further comprising at least 3 internal corners, and wherein no more than 50%, or no more than 45%, or no more than 40%, or no more than 35%, or no more than 30%, or no more than 25%, or no more than 20%, or no more than 18%, or no more than 16%, or no more than 14%, or no more than 12%, or no more than 10%, or no more than 9%, or no more than 8%, or no more than 7%, or no more than 6%, or no more than 5%, or no more than 4%, or no more than 3%, or no more than 2%, or no more than 1% of the total number of the plurality of shaped abrasive grains or elongated abrasive grains have cracks at the internal corners.

[0125] Embodiment 22. The abrasive grain of embodiment 1, further comprising at least 3 internal corners, and wherein at least 0.01%, or at least 0.5%, or at least 1%, or at least 2%, or at least 3%, or at least 4%, or at least 5%, or at least 8%, or at least 10% of the total number of the plurality of shaped abrasive grains or elongated abrasive grains have cracks at the internal corners.

[0126] Embodiment 23. The abrasive grain of Embodiment 1, further comprising a ceramic material.

[0127] Embodiment 24. The abrasive grain of Embodiment 1, further comprising at least one of a nitride, an oxide, a carbide, a boride, an oxynitride, an oxyboride, diamond, a carbonaceous material, or any combination thereof.

[0128] Embodiment 25. The abrasive grain of Embodiment 1, further comprising an oxide compound or composite, such as aluminum oxide, zirconium oxide, titanium oxide, yttrium oxide, chromium oxide, strontium oxide, silicon oxide, magnesium oxide, rare earth oxides, or any combination thereof.

[0129] Embodiment 26. The abrasive grain of Embodiment 1, further comprising aluminum oxide.

[0130] Embodiment 27. An abrasive article comprising:

[0131] backing;

[0132] an abrasive layer comprising abrasive grains and a binder;

[0133] wherein the abrasive particles have a random rotational orientation;

[0134] The abrasive grains have an overall height H and fracture features located at a height between 55% and 90% of the H.

[0135] Embodiment 28. The abrasive article of Embodiment 27, wherein the abrasive article comprises abrasive grains according to any one of Embodiments 1 to 26.

[0136] Embodiment 29. The abrasive article of Embodiment 27, wherein the abrasive article is comprised of abrasive grains according to any one of Embodiments 1 to 26.

[0137] Embodiment 30. An abrasive article according to embodiment 27, further comprising upstanding portions of abrasive grains having an upright orientation, wherein the upstanding portions comprise at least 10% of the abrasive grains in the total number of the abrasive grains, or at least 20%, or at least 30%, or at least 40%, or at least 50%, or at least 55%, or at least 57%, or at least 60%, or at least 62%, or at least 65%, or at least 67%, or at least 70%, or at least 72%, or at least 75%, or at least 77%, or at least 80%, or at least 82%, or at least 85%, or at least 87%, or at least 90% of the abrasive grains in the total number of the abrasive grains.

[0138] Embodiment 31. An abrasive article according to embodiment 30, wherein the upright portions are no greater than 99.9% of the total number of the abrasive particles, or no greater than 99%, or no greater than 98%, or no greater than 97%, or no greater than 96%, or no greater than 95% of the total number of the abrasive particles.

[0139] Embodiment 32. An abrasive article according to embodiment 27, further comprising an inclined portion having abrasive grains with an inclined orientation, wherein the inclined portion comprises at least 1% of the abrasive grains in the total number of the abrasive grains, or at least 2%, or at least 3%, or at least 4%, or at least 5%, or at least 6%, or at least 7%, or at least 8%, or at least 9%, or at least 10%, or at least 11%, or at least 12%, or at least 13%, or at least 14%, or at least 15%, or at least 16%, or at least 17%, or at least 18%, or at least 20%, or at least 25% of the abrasive grains in the total number of the abrasive grains.

[0140] Embodiment 33. An abrasive article according to embodiment 32, wherein the beveled portion is no more than 90% of the total number of abrasive particles, or no more than 85%, or no more than 80%, or no more than 75%, or no more than 70%, or no more than 65%, or no more than 60%, or no more than 55%, or no more than 50%, or no more than 45%, or no more than 40%, or no more than 35%, or no more than 30%, or no more than 25%, or no more than 20%, or no more than 18%, or no more than 15%, or no more than 12%, or no more than 10% of the total number of abrasive particles.

[0141] Embodiment 34. An abrasive article according to embodiment 27, further comprising a standing portion (Pst) having abrasive particles in a standing orientation and a slanted portion (Psl) having abrasive particles in a slanted orientation, and further comprising a ratio of the standing portion to the slanted portion (Pst / Psl) of at least 1, or at least 1.2, or at least 1.4, or at least 1.6, or at least 1.8, or at least 2.0, or at least 2.2, or at least 2.4, or at least 2.6, or at least 2.8, or at least 3.0, or at least 3.2, or at least 3.4, or at least 3.6, or at least 3.8, or at least 4.0, or at least 4.2, or at least 4.4, or at least 4.6, or at least 4.8, or at least 5.0, or at least 5.2, or at least 5.4, or at least 5.6.

[0142] Embodiment 35. An abrasive article according to embodiment 34, wherein the ratio of the upright portion to the inclined portion (Pst / Psl) is not greater than 100, or not greater than 95, or not greater than 90, or not greater than 80, or not greater than 70, or not greater than 60, or not greater than 50, or not greater than 40, or not greater than 30, or not greater than 20, or not greater than 10.

[0143] Embodiment 36. An abrasive article according to embodiment 27, wherein the abrasive article further comprises a falling portion of abrasive grains having a falling orientation, wherein the falling portion comprises at least 0.1% of the abrasive grains in the total number of the abrasive grains, or at least 0.2%, or at least 0.4%, or at least 0.6%, or at least 0.8%, or at least 1%, or at least 1.5%, or at least 2%, or at least 2.5%, or at least 3%, or at least 3.5%, or at least 4%, or at least 4.5%, or at least 5% of the abrasive grains in the total number of the abrasive grains.

[0144] Embodiment 37. An abrasive article according to embodiment 36, wherein the fallen portion is no more than 20% of the total number of the abrasive particles, or no more than 18%, or no more than 15%, or no more than 12%, or no more than 10%, or no more than 9%, or no more than 8%, or no more than 7%, or no more than 6%, or no more than 5% of the total number of the abrasive particles.

[0145] Embodiment 38. The abrasive article of embodiment 27, further comprising an upright portion (Pst) having upright oriented abrasive particles and a fallen portion (Pf) having fallen oriented abrasive particles, and further having a grit density of at least 2.0, or at least 2.2, or at least 2.4, or at least 2.6, or at least 2.8, or at least 3.0, or at least 3.2, or at least 3.4, or at least 3.6, or at least 3.8, or at least 4.0, or at least 4. 2, or at least 4.4, or at least 4.6, or at least 4.8, or at least 5.0, or at least 5.2, or at least 5.4, or at least 5.6, or at least 5.8, or at least 6.0, or at least 6.2, or at least 6.4, or at least 6.6, or at least 6.8, or at least 7.0, or at least 7.2, or at least 7.4, or at least 7.6, or at least 7.8, or at least 8.0, of the ratio of the upright portion to the fallen portion (Pst / Pf).

[0146] Embodiment 39. An abrasive article according to embodiment 38, wherein the ratio of the upright portion to the fallen portion (Pst / Pf) is not greater than 1000, or not greater than 800, or not greater than 500, or not greater than 200, or not greater than 100, or not greater than 95.

[0147] Embodiment 40. An abrasive article according to embodiment 27, further comprising a slanted portion (Psl) having abrasive particles with an inclined orientation and a fallen portion (Pf) having abrasive particles with a fallen orientation, and further comprising a ratio (Psl / Pf) of the slanted portion to the fallen portion of at least 1, or at least 1.2, or at least 1.4, or at least 1.6, or at least 1.8, or at least 2.0, or at least 2.2, or at least 2.4, or at least 2.6, or at least 2.8, or at least 3.0, or at least 3.2, or at least 3.4, or at least 3.6, or at least 3.8, or at least 4.0, or at least 4.2, or at least 4.4, or at least 4.6, or at least 4.8, or at least 5.0, or at least 5.2, or at least 5.4, or at least 5.6.

[0148] Embodiment 41. An abrasive article according to embodiment 40, wherein the ratio of the inclined portion to the dropped portion (Psl / Pf) is not greater than 100, or not greater than 95, or not greater than 90, or not greater than 80, or not greater than 70, or not greater than 60, or not greater than 50, or not greater than 40, or not greater than 30, or not greater than 20, or not greater than 10, or not greater than 8, or not greater than 6.

[0149] Embodiment 42. An abrasive article according to embodiment 27, further comprising a reverse portion of abrasive grains having a reverse orientation, wherein the reverse portion comprises at least 0.1% of the abrasive grains in the total number of the abrasive grains, or at least 0.2%, or at least 0.4%, or at least 0.6%, or at least 0.8%, or at least 1%, or at least 1.5%, or at least 2%, or at least 2.5%, or at least 3%, or at least 3.5%, or at least 4%, or at least 4.5%, or at least 5% of the abrasive grains in the total number of the abrasive grains.

[0150] Embodiment 43. An abrasive article according to embodiment 42, wherein the reversal portion is no more than 20% of the total number of abrasive particles, or no more than 18%, or no more than 15%, or no more than 12%, or no more than 10%, or no more than 9%, or no more than 8%, or no more than 7%, or no more than 6%, or no more than 5% of the total number of abrasive particles.

[0151] Embodiment 44. An abrasive article according to embodiment 27, further comprising a standing portion (Pst) having abrasive particles in a standing orientation and an inverted portion (Pi) having abrasive particles in an inverted orientation, and further comprising a ratio of the standing portion to the inverted portion (Pst / Pi) of at least 1, or at least 2.0, or at least 3.0, or at least 4.0, or at least 5.0, or at least 6, or at least 7, or at least 8, or at least 9, or at least 10, or at least 12, or at least 15, or at least 18, or at least 20, or at least 25, or at least 30, or at least 40, or at least 50.

[0152] Embodiment 45. An abrasive article according to embodiment 44, wherein the ratio of the upright portion to the reverse portion (Pst / Pi) is not greater than 100, or not greater than 95, or not greater than 90, or not greater than 80, or not greater than 70, or not greater than 60, or not greater than 50, or not greater than 40, or not greater than 30, or not greater than 20, or not greater than 10, or not greater than 8, or not greater than 6.

[0153] Embodiment 46. An abrasive article according to embodiment 27, wherein the abrasive article further comprises a slanted portion (Psl) having abrasive particles with a slanted orientation and an inverted portion (Pi) having abrasive particles with an inverted orientation, and further comprises a ratio of the slanted portion to the inverted portion (Psl / Pi) of at least 0.6, or at least 0.7, or at least 0.8, or at least 0.9, or at least 1, or at least 1.2, or at least 1.4, or at least 1.6, or at least 1.8, or at least 2.0, or at least 2.2, or at least 2.4, or at least 2.6, or at least 2.8, or at least 3.0, or at least 3.2, or at least 3.4, or at least 3.6, or at least 3.8, or at least 4.0, or at least 4.2, or at least 4.4, or at least 4.6, or at least 4.8, or at least 5.0, or at least 5.2, or at least 5.4, or at least 5.6.

[0154] Embodiment 47. An abrasive article according to embodiment 46, wherein the ratio of the inclined portion to the reverse portion (Psl / Pi) is not greater than 100, or not greater than 95, or not greater than 90, or not greater than 80, or not greater than 70, or not greater than 60, or not greater than 50, or not greater than 40, or not greater than 30, or not greater than 20, or not greater than 10, or not greater than 8, or not greater than 6, or not greater than 4, or not greater than 3, or not greater than 2, or not greater than 1.5.

[0155] Embodiment 48. An abrasive article according to embodiment 27, wherein the abrasive article further comprises a falling portion (Pf) of abrasive particles having a falling orientation and an inverted portion (Pi) of abrasive particles having an inverted orientation, and further comprises a ratio of the falling portion to the inverted portion (Pf / Pi) of at least 0.6, or at least 0.7, or at least 0.8, or at least 0.9, or at least 1, or at least 1.2, or at least 1.4, or at least 1.6, or at least 1.8, or at least 2.0, or at least 2.2, or at least 2.4, or at least 2.6, or at least 2.8, or at least 3.0, or at least 3.2, or at least 3.4, or at least 3.6, or at least 3.8, or at least 4.0, or at least 4.2, or at least 4.4, or at least 4.6, or at least 4.8, or at least 5.0.

[0156] Embodiment 49. An abrasive article according to embodiment 48, wherein the ratio of the falling portion to the reversal portion (Pf / Pi) is not greater than 100, or not greater than 95, or not greater than 90, or not greater than 80, or not greater than 70, or not greater than 60, or not greater than 50, or not greater than 40, or not greater than 30, or not greater than 20, or not greater than 10, or not greater than 8, or not greater than 6, or not greater than 4, or not greater than 3, or not greater than 2, or not greater than 1.5.

[0157] Embodiment 50. An abrasive article according to embodiment 27, further comprising upright portions (Pst) of abrasive grains having an upright orientation and inclined portions (Psl) of abrasive grains having an inclined orientation, and further comprising a percentage of good orientation represented by the sum of the upright portions (%) plus the inclined portions (%) relative to all of the abrasive grains (i.e., 100%), wherein the percentage of good orientation is at least 60%, or at least 62%, or at least 65%, or at least 67%, or at least 70%, or at least 72%, or at least 75%, or at least 77%, or at least 80%, or at least 82%, or at least 85%, or at least 87%, or at least 90%, or at least 92%, or at least 95%.

[0158] Embodiment 51. An abrasive article according to embodiment 50, wherein the percentage of good orientation is no greater than 99.9%, or no greater than 99%, or no greater than 98%, or no greater than 97%, or no greater than 96%, or no greater than 95%.

[0159] Embodiment 52. A method of using an abrasive article, the method comprising:

[0160] Using the abrasive product to grind a workpiece in a specific grinding direction,

[0161] wherein the abrasive article comprises a backing:

[0162] The abrasive layer comprises abrasive grains and a binder;

[0163] wherein a first portion of the abrasive particles have a rotational orientation of 45 to 90 degrees relative to the grinding direction;

[0164] The second portion of the abrasive particles has a rotational orientation of 0 to 45 degrees relative to the grinding direction.

[0165] wherein at least 10% of said first portion of said abrasive particles are fractured;

[0166] wherein no greater than 90% of the second portion of the abrasive particles are fractured.

[0167] Embodiment 53. The method of Embodiment 52, wherein the abrasive article is the abrasive article of any one of Embodiments 27 to 51.

[0168] Embodiment 54. The method of Embodiment 52, wherein the abrasive particles comprise abrasive particles according to any one of Embodiments 1 to 26.

[0169] Embodiment 55. A method according to Embodiment 52, wherein at least 20% of the first portion of the abrasive particles are broken, or at least 30%, or at least 40%, or at least 50%, or at least 60%, or at least 70%, or at least 80%, or at least 90% of the first portion of the abrasive particles are broken.

[0170] Embodiment 56. A method according to Embodiment 52, wherein less than 99% of the first portion of the abrasive particles are broken, or less than 90%, or less than 80%, or less than 70%, or less than 60%, or less than 50%, or less than 40%, or less than 30%, or less than 20%, or less than 10% of the first portion of the abrasive particles are broken.

[0171] Embodiment 57. A method according to Embodiment 52, wherein less than 80% of the second portion of the abrasive particles are broken, or less than 70%, or less than 60%, or less than 50%, or less than 40%, or less than 30%, or less than 20%, or less than 10% of the second portion of the abrasive particles are broken.

[0172] Embodiment 58. A method according to Embodiment 52, wherein at least 10% of the first portion of the abrasive particles are broken, or at least 20%, or at least 30%, or at least 40%, or at least 50%, or at least 60%, or at least 70%, or at least 80%, or at least 90% of the second portion of the abrasive particles are broken.

[0173] Embodiment 59. The abrasive grain of embodiment 1, wherein the fracture feature has a thickness of at least 100 microns, or at least 110 microns, or at least 120 microns, or at least 130 microns, or at least 140 microns, or at least 150 microns, or at least 160 microns, or at least 170 microns, or at least 180 microns, or at least 190 microns, or at least 200 microns, or at least 210 microns, or at least 220 microns, or at least 230 microns, or at least 240 microns, or at least 250 microns, or at least 260 microns, or at least 270 microns, or a radius of curvature of at least 280 microns, or at least 290 microns, or at least 300 microns, or at least 310 microns, or at least 320 microns, or at least 330 microns, or at least 340 microns, or at least 350 microns, or at least 360 microns, or at least 370 microns, or at least 380 microns, or at least 390 microns, or at least 400 microns, or at least 410 microns, or at least 420 microns, or at least 430 microns, or at least 440 microns, or at least 450 microns, or at least 460 microns, or at least 470 microns, or at least 480 microns.

[0174] Embodiment 60. The abrasive grain of Embodiment 1, wherein the fracture feature has a radius of curvature of not greater than 3000 microns, or not greater than 2500 microns, or not greater than 2000 microns, or not greater than 1900 microns, or not greater than 1800 microns, or not greater than 1700 microns, or not greater than 1600 microns, or not greater than 1500 microns, or not greater than 1400 microns, or not greater than 1300 microns, or not greater than 1200 microns, or not greater than 1100 microns, or not greater than 1000 microns, or not greater than 900 microns, or not greater than 800 microns, or not greater than 700 microns, or not greater than 600 microns, or not greater than 500 microns.

[0175] Embodiment 61. The abrasive grain of Embodiment 1, wherein the fracture feature has an indentation radius of curvature of at least 5 microns, or at least 10 microns, or at least 15 microns, or at least 20 microns, or at least 25 microns, or at least 30 microns, or at least 35 microns, or at least 40 microns, or at least 45 microns, or at least 50 microns.

[0176] Embodiment 62. An abrasive particle according to embodiment 1, wherein the fracture feature has an indentation radius of curvature of not greater than 100 microns, or not greater than 90 microns, or not greater than 80 microns, or not greater than 70 microns, or not greater than 60 microns, or not greater than 50 microns, or not greater than 40 microns, or not greater than 30 microns, or not greater than 20 microns.

[0177] Example

[0178] Respectively as Figures 11A to 11G The abrasive particles S1, S2, S3, S4, S5, S6 and CS1 with the features shown in Table 1 have von Mises stress (von Mises stress) measured via finite element analysis (FEA) software in different scenarios simulating oriented grinding facing the front and oriented grinding facing the side. Particles S1 and S2 have fracture features on the main surface or the front surface. Particles S3 and S4 have fracture features on the side surface. Particle S5 has a curved fracture feature on both main surfaces or the front surface. Particle S6 has a single curved fracture feature on the main surface or the front surface of the body. The radius of curvature of particles S5 and S6 is determined by superimposing the best fit circle on the curvature of the fracture feature and using ImageJ to determine the radius of the best fit circle to accurately measure the best fit circle, as shown in Figure 14 As can be seen, the radius of curvature of the fracture features of S5 and S6 is 470 microns. All particles S1 to S6 have fracture features defined by a semicircular indentation with an indentation curvature radius of 15 microns. Figures 11A to 11GAs shown in , the boundary conditions are set in the middle of the particle. To simulate the orientation grinding facing the front, a tension of 4.7 Newtons and a normal force of 7.8N are applied. To simulate the orientation grinding facing the side, a tension of 1.35 Newtons and a normal force of 1.5N are applied. The forces chosen reflect the forces that the particles are subjected to under conventional working conditions. An image showing the stresses generated when the orientation faces the front can be found in Figures 12A to 12G , while the results for the sideways orientation can be found in Figures 13A to 13G Found in.

[0179] Table 1

[0180]

[0181] To minimize milling energy in continued use, the particles desirably undergo accelerated fracture when used in front-facing oriented milling, but not when used in side-facing oriented milling.

[0182] The present application represents a departure from the prior art. While certain publications have disclosed the desire to orient shaped abrasive particles in certain orientations, these publications do not achieve the degree of orientation as disclosed in the present application. Notably, it is apparent that conventional coated abrasives have a significant portion of abrasive particles placed in an undesirable orientation. The industry continues to desire a system and method that can achieve a greater degree of control over the orientation of abrasive particles in coated abrasives. The systems and methods disclosed herein enable the formation of coated abrasive articles that have greater control over the orientation of particles on a backing for the manufacture of coated abrasive articles. In addition, the systems and methods herein can facilitate improved fine-tuning control of certain orientations, such as control of the upright, tilted, fallen, and reversed orientation of the grains.

[0183] The subject matter disclosed above is to be considered illustrative and not restrictive, and the appended claims are intended to cover all such modifications, enhancements, and other embodiments that fall within the true scope of the invention. Therefore, to the maximum extent allowed by law, the scope of the present invention is to be determined by the broadest permissible interpretation of the appended claims and their equivalents, and shall not be restricted or limited by the foregoing detailed description.

[0184] The Abstract is provided to comply with patent law and is submitted with the understanding that it will not be used to interpret or limit the scope or meaning of the claims. Additionally, in the foregoing detailed description, various features may be grouped together or described in a single embodiment for the purpose of streamlining the disclosure.

[0185] This disclosure should not be interpreted as reflecting an intention that the claimed embodiments require more features than are expressly recited in each claim. Rather, as the following claims reflect, the inventive subject matter may be directed to less than all features of any of the disclosed embodiments. Thus, the following claims are incorporated into the Detailed Description, with each claim independently defining separately claimed subject matter.

Claims

1. Abrasive particles, comprising: a first major surface, the second major surface, a side surface between the first main surface and the second main surface, Total height H, and at least one fracture feature located at a height of 55%H to 90%H. 2 . The abrasive particle of claim 1 , wherein the at least one fracture feature is located on the first major surface. 3 . The abrasive particle of claim 1 , wherein the abrasive particle comprises at least one fracture feature on the first major surface and at least one fracture feature on the second major surface. The abrasive particle of claim 1 , wherein the at least one fracture feature is on a side surface.

5. The abrasive particle of claim 1, wherein the abrasive particle is a shaped particle or an elongated particle having a length (l), a width (w), and a thickness (t), wherein the width > the thickness and the length > the thickness.

6. The abrasive particle of claim 1, wherein the fracture feature has a radius of curvature of at least 100 microns and no greater than 3000 microns.

7. An abrasive article, comprising: backing; an abrasive layer comprising abrasive grains and a binder; wherein the abrasive particles have a random rotational orientation; The abrasive grains have an overall height H and fracture features located at a height between 55% and 90% of the H.

8. The abrasive article of claim 7, further comprising upstanding portions having abrasive grains in an upright orientation, wherein the upstanding portions comprise at least 10% of the abrasive grains in the total number of the abrasive grains.

9. The abrasive article according to claim 7, further comprising upright portions (Pst) of abrasive grains having upright orientation and inclined portions (Psl) of abrasive grains having inclined orientation, and further having a percentage of good orientation represented by the sum of the upright portions (%) plus the inclined portions (%) relative to all abrasive grains in the abrasive grains (i.e., 100%), wherein the percentage of good orientation is at least 60%.

10. The abrasive article of claim 7, wherein the percentage of good orientation is no greater than 99.9%, or no greater than 99%, or no greater than 98%, or no greater than 97%, or no greater than 96%, or no greater than 95%.

11. A method of using an abrasive article, the method comprising: Using the abrasive product to grind a workpiece in a specific grinding direction, wherein the abrasive article comprises a backing: The abrasive layer comprises abrasive grains and a binder; wherein a first portion of the abrasive particles have a rotational orientation of 45 to 90 degrees relative to the grinding direction; wherein the second portion of the abrasive particles has a rotational orientation of 0 to 45 degrees relative to the grinding direction; wherein at least 10% of said first portion of said abrasive particles are fractured; wherein no greater than 90% of the second portion of the abrasive particles are fractured.

12. The method of claim 11, wherein the abrasive article is the abrasive article of claim 9.

13. The method of claim 11, wherein the abrasive particles comprise the abrasive of claim 1.

14. The method of claim 11, wherein at least 20% of the first portion of the abrasive particles are fractured.

15. The method of claim 11, wherein less than 80% of the second portion of the abrasive particles are fractured.

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