Wheel hub for vehicles and method for manufacturing a wheel hub

Abstract

The present invention discloses a wheel hub for land vehicles wherein the geometry of the wheel hub has been improved compared to its equivalents of the prior art, aiming to provide notable improvements in the mechanical and physicochemical properties thereof, as well as in its manufacturing method and application to a vehicle axle. The present invention also discloses considerable improvements in reducing the weight of the wheel hub compared to the prior art, resulting in exponential performance improvements. The present invention pertains more specifically to the fields of mechanical engineering, materials engineering and metallurgy.

Description

Wheel hub for vehicles and wheel hub manufacturing process. Field of Invention

[0001] The present invention falls within the fields of mechanical engineering, materials engineering and metallurgy and discloses a wheel hub for land vehicles. Background of the Invention

[0002] The wheel hub is a component of utmost importance for the vehicle, generally presented in two configurations: a more robust configuration of wheel hubs is responsible for transmitting torque between the axle and the vehicle wheel, originating from the vehicle's engine; while a simpler configuration of the wheel hub is intended for passive axles, which allow the wheel to rotate relative to the vehicle's axle as a function of its movement along the ground.

[0003] Given its application, the wheel hub is frequently exposed to severe and multidirectional stresses, such as impacts against potholes and obstacles on the road (when in off-road conditions), as well as inclement weather and chemical aggression caused by rain, puddles, mud, and other dirt.

[0004] Therefore, geometric optimization of a wheel hub is highly desirable in order to better withstand mechanical stresses, contributing to increased vehicle lifespan and safety.

[0005] There is also a general interest in the automotive sector to reduce the weight of vehicle components, particularly for commercial freight transport vehicles, where reducing the vehicle's own weight results in reduced energy consumption (electricity or fuel) when running empty, as well as enabling an increase in its load capacity.

[0006] The wheel hubs of the prior art are predominantly manufactured from cast iron. Therefore, it is also desirable to achieve manufacturing processes that contribute to gaining or maintaining the mechanical properties of the final part without compromising the process.

[0007] The desired improvement in mechanical properties of a metal part can be achieved by using particles that enhance the desired characteristic. However, incorporating particles into molten metals is a technical challenge that has not yet been satisfactorily resolved and is the subject of intensive research.

[0008] In the specific field of cast iron, various approaches have been studied and attempted to improve the properties of the final product. One approach is to try to incorporate nanoparticles of various materials. However, the large-scale use of nanoparticles still faces multiple limitations, starting with the unavailability of nanoparticle preparations with high concentration, purity, precise particle size distribution, or even simple availability in large quantities. Furthermore, there are several other technical problems that limit the industrial use of nanoparticles, including the tendency to aggregate, the difficulty of dispersion, the risks associated with eventual dispersion in the air / environment, and the still poorly understood effects resulting from human or animal contact with nanoparticles.

[0009] The problem of difficulty in mixing / dispersing / homogenizing additives, particularly those containing nanoparticles, in the processing of metals and special steels has been known for some time, with different approaches to try to solve it. The present invention shows a solution to this problem.

[0010] Additionally, applications of said metallic materials are highly desirable. Therefore, the present invention also addresses highly desirable and necessary applications in the state of the art.

[0011] In the search for the state of the art in scientific and patent literature, the following documents were found that relate to... theme:

[0012] Document CN207403491 U refers to a utility model for a wheel hub assembly, focusing on its internal oil seal and promoting a high-performance, wear-resistant wheel hub geometry. The internal geometry of the hub for the bearing assembly arrangement is also described. The utility model aims to reduce total costs by reducing maintenance mileage intervals and maintenance complexity compared to a conventional wheel hub assembly. Geometric differences are observed in the claims of this patent application compared to CN207403491 U, such that the aforementioned prior art does not allow for anticipating the optimized geometric characteristics achieved by the present invention, nor does it suggest the use of the metal alloy proposed herein for its production.

[0013] Document US10800205B2 discloses a wheel hub for a passive axle of a cargo vehicle. A central flange extends radially outward from the cylindrical body at a location between the pair of bearing receiving holes. The wheel hub provides sufficient strength and minimizes weight by incorporating specific longitudinal profiles and ratios and / or relationships of various dimensions of the cylindrical portion. US10800205B2 further discloses external protrusions 320 and internal cavities 140 that are not present in the geometry proposed by the present invention. Geometric differences are observed in the claims of the present patent application compared to US10800205B2, such that the aforementioned prior art does not allow one to anticipate the optimized geometric characteristics achieved by the present invention, nor does it suggest the use of the metal alloy proposed herein for its production.

[0014] Document USD470447S presents an industrial design registration for the geometry of a wheel hub. This geometry is defined by a cylinder with a central flange. The periphery of this flange comprises through holes and cavities interspersed between the through holes. One of the The ends of the cylinder are equipped with a face with holes for receiving spindles, forming protrusions on the periphery of the cylinder, which extend to the central flange. Geometric differences are observed in the material claimed in the claims of the present patent application compared to USD470447S, such that the aforementioned prior art does not allow anticipating the optimized geometric characteristics achieved by the present invention, nor does it suggest the use of the metallic alloy proposed here for its production.

[0015] Brazilian patent application BR PI1101389 discloses a pre-assembled wheel hub assembly having all standard components (including inner and outer bearings, spacer, and lubricant seal) pre-assembled within the hub at the manufacturing facility. The BR PI1101389 hub assembly is pre-assembled with the spindle nut assembly pre-positioned and fixed to the hub, and has no separate or loose parts, facilitating shipping and installation of the hub assembly. Installation requires only placing the new hub assembly over the spindle and tightening the pre-positioned retaining nut, installed at the factory. Geometric differences are observed in the material claimed in the present patent application compared to BR PH 101389, such that the aforementioned prior art does not allow for anticipating the optimized geometric characteristics achieved by the present invention, nor does it suggest the use of the metal alloy proposed herein for its production.

[0016] Brazilian patent application BR PI0615435-2 discloses a wheel hub for a heavy-duty vehicle and the bearing arrangement for receiving the axle in the center of the wheel hub, which is relatively short and lightweight, rotatably mounted in the bearings, so that the wheel end assembly selectively accommodates a standard tire configuration, dual wheel, and a wide tire configuration, single wheel. Geometric differences are observed in the claims of the present patent application compared to BR PI0615435-2, such that the aforementioned prior art does not allow for anticipating the optimized geometric characteristics achieved by the present invention, nor does it suggest the use of the metal alloy proposed herein for this purpose. your production.

[0017] Document CN105414497 details the technical difficulties of dispersing additives in the manufacture of special steels. This document discloses a device specifically developed to solve this problem, comprising a pipe, a feeder with a valve welded to the side of an opening, and a thin, sealed, welded pipe with its end directed towards the center of the opening of the other pipe, so as to enable the insufflation of air or argon to create negative pressure and thus allow the addition of fine additive powders into the liquid (molten) steel. The device provides for the adjustment of the uniform addition of the additive. It does not disclose or anticipate the present invention.

[0018] Document JP3321491, entitled “Method for adding rare earth element to molten steel and additive”, discloses a safe way to add an additive to molten steel. The additive is prepared by filling a container with a powder of an alloy containing rare earths, copper, and aluminum. The container is made from a hollow bar of carbon steel or stainless steel. The method of adding the additive consists of continuously adding the additive to the molten steel during the casting phase. It does not disclose or anticipate the present invention.

[0019] Document US4892580 discloses an additive in the form of lead-containing filaments for obtaining modified steels. The additive is presented in the form of filaments consisting of a metallic coating and a finely divided material, which comprises metallic lead or lead alloys, in addition to a material that releases CO2 at the temperature of the molten steel. It does not disclose or anticipate the present invention.

[0020] Document RU2569621 discloses a method for producing niobium-containing steel. Said method includes a step of melting the steel and forming a 200 mm thick layer in a receptacle. During the treatment of the metal outside the furnace, ferroniobium is added in a proportion of 0.01 to 1 kg per ton of metal. It does not disclose or anticipate the present invention.

[0021] US patent document 3860777 discloses a process for welding steels. Low alloy containing niobium. In the aforementioned document, weld deposits of improved strength and hardness are obtained when compared to previously known counterparts. The process involves adding controlled amounts of vanadium and / or titanium to the molten metal, along with other alloying elements, in order to provide the formation of a deposit whose concentration is controlled in comparison to the concentration of niobium present. It does not disclose or anticipate the present invention.

[0022] Patent document WO 9222675 discloses a ferroniobium alloy and a niobium additive for steel, cast iron, and other metal alloys. The ferroniobium alloy has a microstructure comprising a eutectic matrix (E) and a primary constituent (N) as a niobium-rich solid solution, which requires a chemical composition of 75 to 95% niobium, 5 to 25% iron, with the following maximum impurity percentages: tantalum 0.1%, silicon 3%, aluminum 1%, and tin 0.15%. This additive is useful for adding niobium to steels, cast iron, and other materials. It does not disclose or anticipate the present invention.

[0023] Patent application BR 102022002639-4, filed by IHR in February 2022 with the same inventors, discloses a premix useful for the use of nanoparticle preparations of various materials. The aforementioned document, incorporated herein by reference, describes a nanoparticle premix with a peculiar composition, purity, and particle size profile, useful in a variety of applications and solving several technical problems, including facilitating dispersion in other substances and facilitating use in industrial processes. It does not disclose or anticipate the present invention.

[0024] Luiz, TM's dissertation (2019) (Synthesis of Nb2O5 nanoparticles for application in materials hardened by oxide dispersion) presents a material formed from pure Fe (i.e., 99.6% purity) comprising a reinforcement of Nb2O5 nanoparticles at concentrations of 0.25, 0.5, 1.0, 5.0, and 10.0 wt%. The matrix used in the dissertation was pure iron, differing substantially from the composition of cast iron, as well as completely different from the process of the present invention, which is applied... Cast iron.

[0025] The article by Bedolla-Jacuinde A. and Hernandez BX (2003) (Effect of niobium in medium alloyed ductile cast irons) discloses a process for obtaining a ductile nodular cast iron comprising the addition of niobium particles. However, unlike the present design, the Fe-Nb particles are added to the molten iron before molding in green sand. Additionally, the aluminum mentioned in this document is used for alloy deoxidation, a use that differs from the approach employed in the present invention.

[0026] Based on the literature reviewed, no documents were found that anticipated or suggested the teachings of the present invention.

[0027] Thus, in summary, an objective of the present invention is to promote wheel hubs for cargo transport vehicles whose geometry is so optimized as to provide wheel hubs for drive axles that have a slim geometry like the wheel hubs of a passive axle. Summary of the Invention

[0028] Thus, it is an objective of the present invention to achieve an optimized wheel hub geometry that allows for a reduction in its mass compared to its equivalents in the art, but without the mass reduction resulting in performance impairment. The inventors achieved such an optimized geometry through extensive study of the critical regions of mechanical stress in a wheel hub and progressive topological optimization of the part, considering an increase in material mass in the regions of higher mechanical stress and a reduction in mass in the regions of lower stress.

[0029] A geometry is also proposed that is applicable in large-scale production through the casting process.

[0030] Furthermore, the inventors also propose the use of an iron alloy enriched with an additive material that promotes gains in mechanical properties. and the physical-chemical properties of the wheel hub with optimized geometry.

[0031] Compared to prior art products and patent publications, the present invention features optimized geometry that enables gains in mechanical properties of the wheel hub, such as gains in yield strength, tensile strength, and elongation. The simultaneous increase in all three tested properties is particularly surprising, which is counterintuitive for someone skilled in the art. Furthermore, it allows for a reduction in shrinkage cavities, better homogenization of particles in the casting, standardization of metal alloys (baseline), and / or the production of parts with complex geometries.

[0032] Additionally, through the use of a special metallic alloy, the present invention makes it possible to modulate the mechanical properties of a metallic material, such as non-limiting yield strength, tensile strength and / or elongation.

[0033] Finally, it is also worth highlighting the considerable reduction in the weight of parts produced using the present invention compared to equivalent parts of the prior art, and the combination of weight reduction along with improvements in the mechanical properties of the part of the present invention results in an exponential gain in performance when compared to parts of the prior art.

[0034] In a first object, the present invention provides a wheel hub for land vehicles for transporting cargo comprising a cylindrical body having a flange (3) on its outer diameter, wherein a first end of the cylindrical body is provided with a plurality of ribs (1) arranged around its outer wall, each rib (1) being spaced from the next rib (1) by a recess (2), each rib (1) being equidistant from the adjacent ribs (1), such that each rib (1) and each recess (2) extend axially from the first end of the wheel hub to a convex region (5.1) of the wheel hub, where the outer diameter of the cylindrical body progresses until it reaches the flange (3).

[0035] In a second object, the present invention discloses a process for manufacturing a wheel hub for land vehicles for transporting cargo comprising at least the steps of: preparing a casting mold with a geometry intended to produce a wheel hub having a flange (3) on its outer diameter, wherein a first end of the cylindrical body is provided with a plurality of ribs (1) arranged around its outer wall, each rib (1) being spaced from the next rib (1) by a recess (2), all ribs (1) being equidistant from each other, so that each rib (1) and each recess (2) extend axially from the first end of the wheel hub to a convex region (5).1) of the wheel hub, where the outer diameter of the cylindrical body progresses until it reaches the flange (3); preparation of a metal alloy formed by iron and a predefined mass quantity of an aggregate material; melting of the metal alloy and filling of the mold with the molten alloy; and removal of the part from the mold with desired geometric characteristics.

[0036] In a third object, the present invention provides a vehicle drive axle comprising at least one wheel hub at at least one end of the drive axle, said wheel hub having a geometry as defined above.

[0037] These and other objects of the invention will be immediately appreciated by those skilled in the art and will be described in detail below. Brief Description of the Figures

[0038] The following figures are presented:

[0039] Figure 1 shows a front perspective view of a first preferred and non-limiting embodiment of the wheel hub of the present invention.

[0040] Figure 2 shows a rear perspective view of the wheel hub embodiment of the present invention illustrated in Figure 1.

[0041] Figure 3 shows a side view of the wheel hub embodiment of the present invention illustrated in Figure 1.

[0042] Figure 4 shows a front view of the wheel hub embodiment of the present invention illustrated in Figure 1.

[0043] Figure 5 shows a drawing of section AA indicated by Figure 4.

[0044] Figure 6 shows region D highlighted in Figure 5.

[0045] Figure 7 shows region E highlighted in Figure 5.

[0046] Figure 8 shows, in both (a) and (b), the directions of force application for carrying out the tests and trials on the wheel hub of figures 1 - 7.

[0047] Figure 9 shows a graph of the maximum principal stresses obtained in an alternating bending test, comparing different cube configurations from Figures 1-7.

[0048] Figure 10 shows the results of the stresses obtained in a clamping force test with the flat drum, in (a) front view and in (b) rear view.

[0049] Figure 11 shows the results of the stresses obtained in a clamping force test with the flat drum, highlighting the maximum stresses in specific regions of the hub, where (a) shows the front view and (b) the rear view.

[0050] Figure 12 shows the results of the stresses obtained in a clamping force test with the flat drum, detailing the flange region.

[0051] Figure 13 shows the results of the stresses obtained in a positive bending test with the flat drum, in (a) front view and in (b) rear view.

[0052] Figure 14 shows the results of the stresses obtained in a positive bending test with the flat drum, specifically in the flange region.

[0053] Figure 15 shows the results of the stresses obtained in a tensile test in an alternating manner with the flat drum, in (a) in the front view and in (b) in the back view.

[0054] Figure 16 shows the results of the stresses obtained in a tensile test performed alternately with the flat drum, specifically in the region of the flange.

[0055] Figure 17 shows the results of the stresses obtained in a clamping force test with the drum tilted, in (a) in the front view and in (b) in the rear view.

[0056] Figure 18 shows the results of the stresses obtained in a clamping force test with the drum tilted in detail in the flange region.

[0057] Figure 19 shows the results of the stresses obtained in a positive bending test with the drum tilted, in (a) front view and in (b) rear view.

[0058] Figure 20 shows the stress results obtained in a positive bending test with the drum tilted, specifically in the flange region.

[0059] Figure 21 shows the results of the stresses obtained in an alternating tension test with the drum tilted, in (a) in the front view and in (b) in the back view.

[0060] Figure 22 shows the results of the stresses obtained in an alternating tension test with the drum tilted, specifically in the flange region.

[0061] Figure 23 shows a perspective view of a second embodiment of the wheel hub of the present invention.

[0062] Figure 24 shows a rear perspective view of the wheel hub embodiment illustrated in Figure 23.

[0063] Figure 25 shows a front view of the wheel hub embodiment illustrated in Figure 23.

[0064] Figure 26 shows a computational structural analysis of the bearing embedding for the wheel hub illustrated in Figure 23, indicating the maximum principal stresses in MPa.

[0065] Figure 27 shows a computational structural analysis of the bearing embedding for the wheel hub illustrated in Figure 23, indicating the equivalent von Mises stresses in MPa.

[0066] Figure 28 shows a computational structural analysis of the test. torsion for the construction of the wheel hub illustrated in figure 23, indicating the displacement in mm.

[0067] Figure 29 shows a computational structural analysis of a torsion test for the wheel hub illustrated in Figure 23, indicating the maximum principal stresses in MPa.

[0068] Figure 30 shows a computational structural analysis of a torsion test for the wheel hub illustrated in Figure 23, indicating the equivalent von Mises stresses in MPa.

[0069] Figure 31 shows a computational structural analysis of a bending test for the wheel hub illustrated in Figure 23, indicating the displacement in mm.

[0070] Figure 32 shows a computational structural analysis of a bending test for the wheel hub illustrated in Figure 23, indicating the maximum principal stresses in MPa.

[0071] Figure 33 shows the boundary conditions assigned for the analyses illustrated by figures 26 and 27, with the wheel hub in transparency and the bearing embedding with 0.15mm interference with the hub diameter and the clamping illustrated by a triangle in one of the through holes (4).

[0072] Figure 34 shows the boundary conditions assigned for the analyses illustrated by figures 28 to 32, where the horizontal arrows illustrate the pre-tensions arranged on the drum bolts and the clamps indicated by triangles and positioned on the edges of the wheels.

[0073] Figure 35 shows a computational fatigue analysis for the wheel hub design illustrated in Figure 23, indicating life cycles.

[0074] Figure 36 shows a photograph of a dynamic test of the wheel hub embodiment of the present invention.

[0075] Figure 37 presents a tensile test graph for an embodiment of a test specimen corresponding to the rib (1) of the wheel hub embodiment of the present invention illustrated in Figure 23.

[0076] Figure 38 presents a tensile test graph for a embodiment of a test specimen corresponding to the recess (2) of the embodiment of the wheel hub of the present invention illustrated by figure 23.

[0077] Figure 39 presents a tensile test graph for an embodiment of a test specimen corresponding to the flange (3) of the wheel hub embodiment of the present invention illustrated in Figure 23.

[0078] Figure 40 presents a tensile test graph for a third embodiment of a test specimen corresponding to the rib (1) of the wheel hub embodiment of the present invention illustrated in Figure 23.

[0079] Figure 41 presents a tensile test graph for a third embodiment of a test specimen corresponding to the recess (2) of the wheel hub embodiment of the present invention illustrated by Figure 23.

[0080] Figure 42 presents a third embodiment of the wheel hub of the present invention in perspective, showing the front, right side and top views.

[0081] Figure 43 shows the third embodiment of the wheel hub of the present invention in perspective, highlighting the rear, left side and top views.

[0082] Figure 44 shows a side view of the third embodiment of the wheel hub of the present invention.

[0083] Figure 45 shows a side view of a longitudinal section of the third embodiment of the wheel hub of the present invention.

[0084] Figure 46 shows a fourth embodiment of the wheel hub of the present invention in perspective, highlighting the front, right side and top views.

[0085] Figure 47 shows the fourth embodiment of the wheel hub of the present invention in perspective, highlighting the rear, left side and top views.

[0086] Figure 48 shows a right side view of the fourth embodiment of the wheel hub of the present invention.

[0087] Figure 49 shows a side view of a longitudinal section of fourth embodiment of the wheel hub of the present invention.

[0088] Figure 50 shows a metallographic analysis image of a prior art cast iron (standard alloy 600 / 3), highlighting the distribution of nodules in the nodular cast iron.

[0089] Figure 51 shows a metallographic analysis image of a cast iron of the present invention (alloy comprising niobium nanoparticles), highlighting the improved distribution of nodules in the nodular cast iron with niobium nanoparticles. Detailed Description of the Invention

[0090] Compared to prior art products, the present invention provides a wheel hub with optimized geometry, resulting in improved mechanical properties. This geometry is compatible with casting manufacturing. The manufacturing process of the wheel hub of the present invention allows for reduced shrinkage cavities, better homogenization of particles in the casting, standardization of metal alloys (baseline), and / or the production of parts with complex geometries.

[0091] Furthermore, it is worth noting that the wheel hub of the present invention is intended for drive axles, but has such an optimized geometry that it resembles wheel hubs for passive axles (commonly used in road implements), which have a slim geometry because they are not subjected to the considerable values ​​of torsional torque that wheel hubs for drive axles (such as the present invention) need to withstand.

[0092] Additionally, the present invention makes it possible to modulate the mechanical properties of a metallic material, such as non-limiting yield strength, tensile strength and / or elongation.

[0093] Finally, it is also worth highlighting the reduction in the weight of parts produced using the present invention, with the combination of weight reduction coupled with improvements in the mechanical properties of the part resulting from this reduction. The present invention results in an exponential gain in performance when compared to prior art parts.

[0094] In the context of the present invention, the term "Niobium particles" encompasses various chemical entities containing Niobium, including metallic Niobium, oxides, hydrates, hydrides, carbides, or nitrides of Niobium, iron Niobium or Niobium alloyed with other metals or transition metals, or combinations thereof. It also includes Niobium pentoxide (Nb2O5), NbC, NbO and FeNb. They may be microparticles, submicroparticles or nanoparticles.

[0095] In a first object, the present invention provides a wheel hub for land vehicles for transporting cargo comprising a cylindrical body provided with a flange (3) on its outer diameter, wherein a first end of the cylindrical body is provided with a plurality of ribs (1) arranged around its outer wall.

[0096] In one embodiment, each rib (1) is spaced from the next rib (1) by a recess (2), all ribs (1) being equidistant from each other. In a preferred embodiment, and not limitingly, the wheel hub of the present invention comprises eight ribs (1) equidistant from adjacent ribs (1), the wheel hub therefore having eight recesses (2). In one embodiment, the number of ribs (1) and recesses (2) of the wheel hub of the present invention may vary, for example, depending on the size and model of the vehicle to which the wheel hub will be attached. In this embodiment, as illustrated in Figure 4, the spacing between subsequent ribs (1) is 45°.

[0097] Each rib (1) and each recess (2) extend axially from the first end of the wheel hub to a convex region (5.1) of the wheel hub, where the outer diameter of the cylindrical body progresses until it reaches the flange (3).

[0098] In one embodiment, each rib (1) is provided with a non-through internal hole for receiving a spindle. In one embodiment, the non-through hole of each rib (1) is a threaded hole, intended to receive a spindle. In another embodiment, each rib (1) is provided with a threaded through hole for receiving a spindle.

[0099] In one embodiment, as illustrated by figures 1 to 7, each rib (1) comprises, at the first end, a tubular portion (1.1) provided with a threaded hole for receiving a spindle.

[0100] In one embodiment, as illustrated by figures 1 to 7, each rib (1) comprises at least one concave section (1.2) disposed between the tubular portion (1.1) and the convex transition region to the flange (3). In this embodiment, the rib (1) is divided into a first cylindrical outer geometry with an internal hole that extends to an approximately central region of the length of the rib (1), towards the flange (3), the section of the rib (1) proximal to the flange (3) having a concave cavity along its length.

[0101] In one embodiment, the concave portion (1.2) of the rib (1) comprises a U-shaped cross-section, which can be defined by two projections that connect the tubular portion (1.1) to the convex region of the flange (3), the cavity between these two projections being a concave cavity.

[0102] As is usually practiced in the art, the wheel hub has sections of varying diameters in its internal through hole, these holes being intended to fit axle components, such as the axle end and bearings. As can be seen in Figure 7, the thickness of the wheel hub of the present invention below the concave portions is considerably thin when compared to other wheel hubs of the prior art. This region of the hub is intended to receive a bearing in its internal hole, so that the concave portions (1.2) contribute significantly to the gain in mechanical properties of this region, this being a region subject to considerable stress.

[0103] In one embodiment, the second end of the cylindrical body, axially opposite to the first end, extends to a second convex region (5.2), where the outer diameter of the cylindrical body progresses until it reaches the flange (3), on a face of the flange (3) opposite the face where the first convex region is located.

[0104] In a preferred embodiment, the first convex region (5.1) comprises concavity facing inwards of the wheel hub, so that the portion closest to the first end of the hub is more vertical than the portion closest to the flange (3), which is more horizontal.

[0105] In this embodiment, the second convex region (5.2) is arranged in the opposite way to the first convex region (5.1), that is, the second convex region (5.2) comprises concavity facing outwards from the wheel hub, so that the portion closest to the first end of the hub is more horizontal than the portion closest to the flange (3), which is more vertical.

[0106] In one embodiment, the flange (3) is provided with a plurality of rounded tabs on its outer diameter, each tab having a through hole (4). In one embodiment, each through hole (4) is intended to receive a spindle.

[0107] In a preferred embodiment, the flange (3) comprises ten tabs, each tab having a through hole (4). In one embodiment, the number of tabs of the flange (3) of the wheel hub of the present invention may vary, for example, depending on the size and model of the vehicle to which the wheel hub will be attached. In a preferred embodiment, the wheel hub of the present invention has four through holes (4) arranged around the flange (3).

[0108] In one embodiment, the tabs are spaced by a valley (4.1), so that the distance between diametrically opposite valleys (4.1) is less than the distance between diametrically opposite through holes (4).

[0109] Even though recesses between flanges with holes in the wheel hub flange are already a configuration used by the previous technique, it is evident that the valleys (4.1) of the wheel hub of the present invention are much more prominent than those practiced in the art, given that the depth of these valleys of The technique usually involves measuring the radius of the through hole in the flange, which clearly differs from the present invention.

[0110] In one embodiment, at least one of the convex regions of the wheel hub comprises at least one protrusion (5). The protrusion (5) aims to promote structural strength gains in the wheel hub of the present invention. In one embodiment, each protrusion (5) is associated with a rib (1).

[0111] In one embodiment, each protrusion (5) is equidistant from the protrusions (5) adjacent to it, so that they are circumferentially equidistant from the previous and subsequent protrusions (5).

[0112] In one embodiment, each protrusion (5) arranged in the second convex region (5.2) is arranged aligned with a flange (3) tab and, consequently, with the through hole (4) of the flange (3). In a preferred embodiment, and not limitingly, the wheel hub has in the second convex region (5.2) the same number of protrusions (5) as the number of through holes (4) of the flange (3). In a preferred embodiment, and not limitingly, there are 10 protrusions in the second convex region (5.2), such that this number varies depending on the vehicle model and wheel hub size.

[0113] In one embodiment, the wheel hub of the present invention comprises four protrusions (5). In one embodiment, the number of protrusions (5) may vary, for example, depending on the size and model of the vehicle to which the wheel hub will be attached.

[0114] In one embodiment, each protrusion (5) arranged in the first convex region (5.1) is arranged aligned with a recess (2). In a preferred embodiment, and not limitingly, in a wheel hub with eight ribs (1) and eight recesses (2), the first convex region (5.1) comprises four protrusions (5).

[0115] In one embodiment, the outer wall of the projection (5) comprises curvature that follows the curvature of the convex region.

[0116] In one embodiment, as illustrated by figures 1 to 7, Both convex regions of the wheel hub comprise a plurality of protrusions (5). In this embodiment, the protrusions (5) facing the ribs (1) have a geometry distinct from the protrusions (5) arranged on the opposite side of the flange (3). In another embodiment, all the protrusions (5) of the wheel hub have the same geometry.

[0117] In one embodiment, as shown in Figure 6, the face of the flange (3) facing the first end of the wheel hub is associated with the first convex region (5.1) by an annular region. The transition region between the vertical face of the flange (3) and the annular region forms a radius R', as illustrated in Figure 6. Between the annular region and the first convex region (5.1) another transition region is formed, which forms a radius R”.

[0118] In one embodiment, R' is defined in a range of 0.2mm to 10mm, more specifically between 1mm and 5mm. In another embodiment, R' is 2mm.

[0119] In one embodiment, R” is defined in a range of 0.2mm to 10mm, more specifically between 1mm and 5mm. In another embodiment, R” is 2mm.

[0120] In a preferred embodiment, and in a non-limiting manner, R' and R” have the same value.

[0121] The R' and R" spokes provide a safety factor to the assembly of the wheel hub of the present invention, as their configuration prevents the wheel from being assembled without first installing the brake.

[0122] Some users of cargo vehicles practice mounting the wheels on passive axles of cargo vehicles without brakes, aiming to save on components. The present invention makes it possible to prevent this improper mounting, since it is only possible to mount the wheel after mounting the brake drum, this arrangement being promoted by the spokes R', R" and the annular region between them.

[0123] In one embodiment, as shown in Figure 6, the face of the flange (3) facing the second end of the wheel hub is associated to the second convex region (5.2) by an arched region of radius R'”. In one embodiment, the value of the radius R'” varies between 2mm and 20mm, more specifically between 5mm and 15mm. In a preferred embodiment, and not limitingly, the value of R'” is 10mm.

[0124] In a preferred embodiment, the present invention features a wheel hub as defined by Figures 1 to 7.

[0125] In a second embodiment, the present invention features a wheel hub with geometry as defined by Figures 23 to 25.

[0126] In a third embodiment, the present invention features a wheel hub as defined by Figures 42 to 45.

[0127] In a fourth embodiment, the present invention features a wheel hub as defined by Figures 46, 47, 48 and 49.

[0128] In one embodiment, the wheel hub of the present invention comprises a cast iron alloy comprising a mass amount of niobium nanoparticles.

[0129] In one embodiment of the wheel hub, the aforementioned niobium nanoparticles are composed of NbO, NbÜ2, or Nb2Ü5.

[0130] In one embodiment of the wheel hub, the aforementioned Niobium nanoparticles are composed of Nb2U5.

[0131] In one embodiment of the wheel hub, the aforementioned mass quantity of niobium nanoparticles comprises a degree of amortization of at least 19%.

[0132] In one embodiment of the wheel hub, the aforementioned mass quantity of nanoparticles preferably comprises an amortization degree of at least 19%, more preferably at least 25%, more preferably at least 30%, more preferably at least 35%, more preferably at least 39%, more preferably at least 40%, more preferably at least 45%, more preferably at least 50%, more preferably an amortization degree of at least 55%, more preferably at least 59%, more preferably at least 65%, and even more preferably a depreciation rate of at least 70%. In a specific embodiment, the depreciation rate is at least 71%, more preferably at least 72%, most preferably at least 73%. In a non-limiting embodiment, the depreciation rate is 74%.

[0133] In one embodiment of the wheel hub, the aforementioned mass quantity of niobium nanoparticles preferably comprises a depreciation rate of at least 39%, preferably a depreciation rate of at least 59%, and even more preferably a depreciation rate of at least 74%.

[0134] Using the Brazilian market as a reference, the average weight of a wheel hub for a truck's drive axle is around 30 kg. The present invention discloses a wheel hub solution with optimized geometry and optimized material which, in combination, allows the weight of each wheel hub to be reduced to around 13 kg, more specifically, 13.4 kg, without any detriment to mechanical or physicochemical performance. On the contrary, the service life and reliability of the wheel hub of the present invention is superior to that currently practiced in the market.

[0135] The tests performed on the wheel hub embodiments of the present invention, illustrated in the figures section, confirm these claims. The examples given later in this report also reinforce these benefits.

[0136] In a second aspect, the present invention discloses a wheel hub manufacturing process comprising the step of producing a metal wheel hub by casting it, having the geometric characteristics defined above.

[0137] More specifically, the manufacturing process for a wheel hub for land cargo transport vehicles of the present invention comprises at least the following steps: preparing a casting mold with a geometry intended to produce a wheel hub having a flange (3) on its outer diameter, where one end of the cylindrical body is endowed with a plurality of ribs (1) arranged around its outer wall, each rib (1) being spaced from the next rib (1) by a recess (2), all ribs (1) being equidistant from each other, so that each rib (1) and each recess (2) extend axially from the first end of the wheel hub to a convex region (5.1) of the wheel hub, where the outer diameter of the cylindrical body progresses until it reaches the flange (3); preparation of a metallic alloy formed by iron and a mass quantity of a predefined binding material; melting of the metallic alloy and filling of the mold with the molten alloy; and removal of the part from the mold with desired geometric characteristics.

[0138] In one embodiment, the process of the present invention comprises at least one step of modulating the mechanical properties of a metallic material from which the wheel hub is manufactured, by incorporating a mass quantity of niobium nanoparticles, wherein said mass quantity of niobium nanoparticles comprises a degree of damping of at least 19%.

[0139] In one embodiment, the aforementioned mass quantity of nanoparticle preferably comprises a depreciation rate of at least 19%, more preferably at least 25%, more preferably at least 30%, more preferably at least 35%, more preferably at least 39%, more preferably at least 40%, more preferably at least 45%, more preferably at least 50%, more preferably a depreciation rate of at least 55%, more preferably at least 59%, more preferably at least 65%, and even more preferably a depreciation rate of at least 70%. In one embodiment, the depreciation rate is at least 71%, more preferably at least 72%, more preferably at least 73%. In a non-limiting embodiment, the depreciation rate is 74%.

[0140] In one embodiment of the process, the aforementioned mass quantity of niobium nanoparticles preferably comprises a degree of amortization of at least 39%, preferably an amortization rate of at least 59%, and even more preferably an amortization rate of at least 74%.

[0141] In a concrete application of the process, the aforementioned mechanical properties that can be modulated are yield strength, tensile strength, elongation, mass, among others.

[0142] The present invention also allows for a concomitant gain in the mechanical properties of yield strength, tensile strength, and elongation, with the concomitant increase in all three tested properties being particularly surprising, which is counterintuitive for someone skilled in the art.

[0143] In one embodiment, the metallic material in question is cast iron.

[0144] In one embodiment, the aforementioned niobium nanoparticles are composed of NbO, NbC, or Nb2Ü5.

[0145] In one embodiment, the aforementioned niobium nanoparticles are composed of Nb2U5.

[0146] In a third object, the present invention provides a vehicle drive axle comprising at least one wheel hub at at least one end of said drive axle, said wheel hub having a geometry as defined above.

[0147] In one embodiment, the wheel hub of the drive axle of the present invention comprises a mass quantity of niobium nanoparticles.

[0148] In one embodiment, the vehicle is a tractor vehicle, for example, without limitation to the scope of the invention, a bus or truck. Examples

[0149] The examples shown here are intended only to illustrate some of the various ways of carrying out the invention, without limiting its scope. Example 1 - Geometric Optimization of the Wheel Hub and Structural Analysis

[0150] After several tests and experiments, a geometric optimization was sought in the wheel hub structure that, in addition to obviously meeting the demands of its mechanical properties, could reduce the total mass of the component. This resulted in the embodiment shown in Figures 1 to 7. In this optimized hub configuration, ribs (1) are arranged on its front part to receive the spindles, where each rib (1) comprises at least one concave section (1.2) located between a tubular portion (1.1) and the convex transition region to the flange (3). The rib (1) is divided into a first cylindrical outer geometry with an internal hole that extends to an approximately central region of the rib's length (1), towards the flange (3), with the section of the rib (1) proximal to the flange (3) having a concave cavity along its length.

[0151] Furthermore, two convex regions are provided, one on each side of the wheel hub, where both regions have a plurality of protrusions (5) formed on the surface. The protrusion (5) aims to promote gains in structural resistance to the wheel hub, so that each protrusion (5) located in the second convex region (5.2) is aligned with a flange (3) and, consequently, with the through hole (4) of the flange (3). Furthermore, each protrusion (5) located in the first convex region (5.1) is aligned with a recess (2).

[0152] Furthermore, as shown in Figure 6, the face of the flange (3) facing the first end of the wheel hub is associated with the first convex region (5.1) by an annular region. The transition region between the vertical face of the flange (3) and the annular region forms a radius R'. Between the annular region and the first convex region (5.1) another transition region is formed, which forms a radius R”. In this specific example, R' = R” = 2 mm was adopted.

[0153] Still in figure 6, the face of the flange (3) facing the second end of the wheel hub is associated with the second convex region (5.2) by an arched region of radius R'”. In this specific example, it was adopted R'” = 10mm.

[0154] As can be seen from Figure 7, the thickness of the wheel hub of the present invention below the concave portions is considerably thin when compared with other wheel hubs of the prior art. This region of the hub is intended to receive a bearing in its inner bore, so the concave portions (1.2) contribute significantly to the gain in mechanical properties of this region. Furthermore, the aforementioned concave section (1.2) allows for a further reduction in the mass of the hub, which reached a total weight of 13.4 kg.

[0155] To perform the structural analysis of the optimized cube, several detailed tests and simulations were carried out, as shown in Figures 8 to 22. The contexts of the analyses were as follows: Analyses were performed considering different shapes of the cube's radii; Analyses were performed considering the flat cube backing, where the cube is bolted; It was defined that the FEA stress results should be similar to the stress values ​​obtained during the durability tests. During these tests, the cube was instrumented with strain gauges on the ribs, which made this model calibration possible; The cube was considered to have nominal thicknesses. Furthermore, as can be seen in Figure 8, force was applied in the positive and negative directions aligned with the guide and fixing hole of the cube.

[0156] Figure 9 shows the maximum principal stresses obtained during an alternating bending test, focusing mainly on specific parts of the cube. In the figure, from left to right, the stresses were obtained in the following regions: Radius R' (blue), Rear Radius R'” (red), Base of the protrusion (5) (green) and Protrusion (5) 25mm from the hole (purple). The stresses were represented in the graph for both the flat and inclined positions of the cube. Furthermore, the Rear Radius R'” was tested with 2mm and 10mm. As can be seen, R'” = 10mm resulted in a lower maximum stress than with R'” = 2mm.

[0157] For stress analysis, the tests were divided into two phases, with the hub and drum in the flat and inclined positions. Furthermore, nominal thicknesses R' = 2mm and R'” = 10mm were adopted. Figure 10 shows the von Mises stresses in a clamping force simulation for the hub in the flat position, where Figure 10 shows the specific behavior in the flange (3) and rib (1). Figure 11 shows the maximum principal stresses, specifically highlighting the regions R', R'”, base of the protrusion and protrusion. The clamping force stresses in the flange are shown in detail in Figure 12.

[0158] A positive bending test was also performed, in which Figure 13 highlights the maximum principal stresses. As can be seen in Figure 13(b), at R'” the maximum stress was 444 MPa and the base at the protrusion reached 346 MPa, these being potential failure points, which were remedied with the solution proposed here. Figure 14 shows the result in detail at the flange.

[0159] Furthermore, Figure 15 shows the results of the maximum principal stresses obtained in an alternating stress application test. As can be seen in Figure 15(a), the region of R' = 2mm reached a stress of 522 MPa. The detail of the flange behavior in this same test is presented in Figure 16.

[0160] The same tests were performed for the hub and drum assembly arranged in an inclined position. Figure 17 shows the von Mises stresses in the hub for a clamping force test. The detail of the resulting stresses in the flange is shown in Figure 18.

[0161] While still in the inclined position, the positive bending test was performed, the results of which for the maximum principal stresses are shown in Figure 19. As can be seen in Figure 19(b), the rear radius R'” reached a maximum stress of 615 MPa, as did the base of the protrusion, which reached 503 MPa. These are regions of potential failure in this type of component, but were overcome in the tests performed with the hub proposed here. Furthermore, the behavior of the flange is shown in detail in Figure 20, where it can be... since the region of radius R'" was the one that reached the highest voltage point, but did not present any faults.

[0162] Finally, figures 21 and 22 show the results of the maximum principal stresses obtained in an alternating voltage application test, with the cube and drum assembly inclined. In this case, as indicated in figure 21 (a), the region with the greatest stress was that of Radius R', which reached 520 MPa.

[0163] The aforementioned simulations, combined with field tests, showed that the wheel hub proposed here withstands the mechanical stresses to which the vehicle is subjected in use and does not present any failures in the aspects analyzed. Example 2 - Structural and Fatigue Analysis of a Wheel Hub with Alternative Optimized Geometry

[0164] The objective of the analysis exemplified here is to evaluate the structural behavior of the optimized wheel hub geometry of the present invention under the application of the respective loads and to provide minimum requirements for the material to be used in the wheel hub.

[0165] To realistically represent the component assembly phase, non-linear simulations were performed, providing greater accuracy to the bolt preloads and bearing interference in the wheel hub.

[0166] Second-order elements were used in the wheel hub in all analyses presented here to accurately represent stresses and strains.

[0167] Simplified wheel and brake drum geometries were considered to accurately represent the rigidity in the wheel hub mounting.

[0168] Conventional screws were used in the technique for modeling the fixations.

[0169] The geometry of the shaft was simplified. Its modeling was done using CBUSH-type elements.

[0170] To connect the CBUSH elements to the rest of the geometry, interpolation elements (RBE3) were used.

[0171] The geometry analyzed in this report is a new version, with some modifications to the wheel hub geometry.

[0172] The wheel hub components were modeled using steel and nodular cast iron (FoFo), with the modulus of elasticity assigned to the steel at a value of 210 GPa and a density of 7850 kg / m³. 3 , while the modulus of elasticity assigned to FoFo is 174 GPa and its density is 7200 kg / m³. 3 .

[0173] The wheels, bolts, and bearings were modeled in steel, while the wheel hub, drum, and cover were modeled in cast iron.

[0174] For the bending test, a load of 35,809 N (8050 lbf) was used, positioned at the end of the axle connected to the wheel hub. For the torsion test, a torsional moment of 2.4 x 10 A 7 N.mm was positioned in the center of the inner surface of the lid.

[0175] As illustrated by figure 33 with the wheel hub in transparency, the boundary conditions assigned for the bearing embedment analyses were an interference of 0.15mm with the hub diameter and the embedment illustrated by a triangle in one of the through holes (4).

[0176] Thus, Figure 26 illustrates the results obtained for maximum principal stresses in MPa, while Figure 27 illustrates the von Mises equivalent stresses in MPa.

[0177] The boundary conditions assigned for the load analyses (torsion and bending, illustrated in Figures 28 to 32) are shown in Figure 34, where the horizontal arrows illustrate the prestressing forces applied to the drum bolts, and the supports are indicated by triangles positioned on the edges of the wheels. Each drum bolt received 250 kN of prestress, while the cover bolts received 100 kN of prestress. The bending load was applied along the Y-axis, and the moment was applied along the X-axis.

[0178] Thus, regarding the torsional load, Figure 28 shows the results obtained for the displacement in mm, while Figure 29 shows the... The results obtained for maximum principal stresses in MPa are shown in Figure 30, and the results obtained for von Mises equivalent stresses in MPa are shown in Figure 30.

[0179] For the bending load, Figure 31 shows the results obtained for the displacement in mm, while Figure 32 shows the results obtained indicating the maximum principal stresses in MPa.

[0180] The stress results from static loads are important for fatigue analysis.

[0181] After test iterations with properties that met the FEA failure criterion, a yield strength of 302 MPa and a fracture strength of 540 MPa were assigned to the theoretical cast iron used. These data were used to generate a Haigh diagram and the SN curve, necessary for fatigue analysis.

[0182] As an influencing factor, a surface roughness of 200 µm was applied.

[0183] For mean stress correction, the Haigh Diagram is used.

[0184] The voltage gradient correction method is also used.

[0185] Thus, the computer program used produces the image illustrated in Figure 35, indicating the life cycles of the wheel hub of the present invention.

[0186] In a global context, the wheel hub meets the criterion of 1,000,000 cycles along its body length. The only regions that showed fewer life cycles were the holes; however, these results can be disregarded as the bolt modeling is simplified and the affected regions have an isolated and localized appearance.

[0187] Thus, the results indicate that there are no negative impacts on stress values ​​and fatigue analysis results due to the change in wheel hub geometry compared to models from the previous technique. On the contrary, it is proven that the geometry of the present invention can promote gains compared to the previous technique, since, for the proposed geometry and based on the material curves generated within the computer program, the The requirements for nodular cast iron are a yield strength greater than or equal to 302 MPa and a tensile strength greater than or equal to 540 MPa.

[0188] Thus, since the values ​​above refer to minimum requirements and are extracted from a material generator that uses the FKM standard and statistical data as a database, the use of enhanced materials, such as the use of Niobium for material doping, can promote improvements in these values. Example 3 - Tensile Strength Test at Room Temperature

[0189] For the present example, two sets of three wheel hub samples were prepared to determine the mechanical properties of predefined regions of the wheel hub. Each set of three samples corresponds to the rib (1), the recess (2) and the flange (3), more precisely to the region of the flange with through hole (4) of the flange (3).

[0190] The tensile tests were conducted at an ambient temperature of 21 °C, relative humidity of 60%, and a speed of 1.5 mm / min. The specimens have a diameter of 10 mm.

[0191] The results of the tensile strength test are illustrated in the table below. It should be noted that sample 6 below represents a specimen with shrinkage, for comparison purposes: Table 1 - Tensile Test Results

[0192] Figure 37 shows a tensile test graph corresponding to sample 1 from Table 1, for an embodiment of a test specimen corresponding to the rib (1) of the wheel hub embodiment of the present invention illustrated by figure 23.

[0193] Figure 38 shows a tensile test graph corresponding to sample 2 from Table 1, for an embodiment of a test specimen corresponding to the recess (2) of the wheel hub embodiment of the present invention illustrated by figure 23.

[0194] Figure 39 shows a tensile test graph corresponding to sample 3 from Table 1, for an embodiment of a test specimen corresponding to the flange (3) of the wheel hub embodiment of the present invention illustrated by figure 23.

[0195] Figure 40 shows a tensile test graph corresponding to sample 4 from Table 1, for a second embodiment of a test specimen corresponding to the rib (1) of the wheel hub embodiment of the present invention illustrated by figure 23.

[0196] Figure 41 shows a tensile test graph corresponding to sample 5 from Table 1, for a second embodiment of a test specimen corresponding to the recess (2) of the wheel hub embodiment of the present invention illustrated by figure 23. Example 4 - Niobium nanoparticle preparation process

[0197] A Labstar LS01 stirred ball mill (Netzsch) was fed with micrometric particles of niobium pentoxide. The process involved high-energy wet milling. The particle suspension was 17.7 wt%, consisting of approximately 3500 g of milliCi water + 10 M NaOH and 750 g of the solid sample, which was prepared and stabilized in the mill's mixing tank at pH 9 and titrated with 10 M NaOH. The milling spheres used were yttria-stabilized zirconia, 400 µm in diameter. The milling chamber was filled to 80% vol. The suspension temperature was below 40 °C. The mill rotation speed was set to 3000 rpm, and grinding was conducted for 8 hours. To stabilize the suspension at pH 9, 10 M NaOH was added during grinding, and samples were taken periodically to measure particle sizes.

[0198] In this example, several embodiments of niobium pentoxide nanoparticle preparations were obtained, with a purity greater than 99%. Commercial niobium pentoxide, with the particle size distribution described in Table 2, was pre-comminuted in a high-energy mill containing yttria-stabilized zirconia spheres with a diameter of 400 µm, in liquid medium and the pH adjusted to 6.6. The mill rotation speed was 3500 rpm and the particle grinding was conducted at a temperature below 40 °C. Table 2 shows the particle size distribution (PSD) of niobium pentoxide input (commercial product) and output from a pre-comminution step. Table 2 - Input DTP (commercial product) and output DTP after pre-comminution.

[0199] The average specific surface area S (m 2 The mass of the particles after the pre-comminution step was 0.32 m / g. 2 / g.

[0200] In one embodiment, the pre-comminuted particles were then fed into a high-energy mill, where conditions similar to those described above were applied, but with 200 µm Zr spheres and milled for different times, until each nanoparticle preparation was obtained. Three different nanoparticle preparations were obtained, each with a defined particle size distribution as described in Table 3. Table 3 - Particle size distribution of three different preparations (C, D and E) of niobium pentoxide nanoparticles.

[0201] Further details on the process for obtaining nanoparticles can be found in patent application BR112023003019 of the inventors of the present application. In the present example and in the examples described below, samples were used that were subjected to 12 hours of grinding.

[0202] Without intending to be bound by theory, it is understood that the samples subjected to 12 hours of grinding, which exhibit a higher degree of amortization (74%), contribute to the surprising effects presented. Example 5 - Process for preparing cast iron alloys

[0203] Details regarding the process for obtaining cast iron alloys can be found in patent application BR102023011061-4 from the same applicant as the present application. In the present example and the examples described below, samples subjected to 12 hours of grinding were used. Example 6 - Example of a wheel hub implementation comprising nanoparticles

[0204] An embodiment of the cast iron wheel hub comprising niobium pentoxide nanoparticles can be found in Figures 42 to 45, with its specific characteristics shown in detail in said figures.

[0205] Among the advantages of the wheel hub of the present invention, in addition to the improved physical properties resulting from the developed alloy material, the reduction in weight compared to prior art wheel hubs stands out, resulting in several advantages for the vehicles to which they are applied.

[0206] In Brazil, commercially sold cast iron wheel hubs weigh around 30 kg. In the United States, commercially sold cast iron wheel hubs weigh around 18 kg. The wheel hub of the first embodiment of the present invention, however, weighs less than 14 kg.

[0207] The combination of weight reduction and improved mechanical properties of the part of the present invention results in an exponential performance gain when compared to prior art wheel hubs. Such a performance gain from the present invention would be readily recognized by a person skilled in the art. Example 7 - Example of a wheel hub implementation comprising nanoparticles

[0208] A third embodiment of the cast iron composite wheel hub comprising niobium pentoxide nanoparticles can be found in Figures 42 to 45, with its specific characteristics shown in detail in said figures.

[0209] Among the advantages of the wheel hub of the present invention, in addition to the improved physical properties resulting from the developed alloy material, the reduction in weight compared to the wheel hubs of [previous invention] can be highlighted. state of the art, which results in several advantages for the vehicles to which they are applied.

[0210] In Brazil, commercially sold cast iron wheel hubs weigh around 30 kg. In the United States, commercially sold cast iron wheel hubs weigh around 18 kg. The wheel hub of the first embodiment of the present invention, however, weighs up to 12 kg, as shown in Figures 1 to 7.

[0211] The combination of weight reduction and improved mechanical properties of the part of the present invention results in an exponential performance gain when compared to prior art wheel hubs. Such a performance gain from the present invention would be readily recognized by a person skilled in the art. Example 8 - Evaluation of mechanical properties

[0212] In order to prove the modulation capabilities of the properties of the method of the present invention, tests were carried out on specimens to evaluate gains in yield strength, tensile strength and average elongation, comparing a standard 600 / 3 alloy and an alloy of the present invention comprising niobium pentoxide nanoparticles, which is detailed in patent application BR102023011061-4 of the same applicant.

[0213] The results are summarized in Table 4 below: Table 4 - Comparison of the mechanical properties of a standard alloy without nano and with nano.

[0214] Based on the results illustrated in Table 4, it would be possible for someone skilled in the art to recognize the surprising effects of using niobium pentoxide nanoparticles according to the method of the present invention, with the concomitant increase in the three properties tested being particularly surprising, which is counterintuitive for someone skilled in the art. Example 9 - Comparative metallographic analysis of nodular cast irons

[0215] Images were also obtained through metallographic analysis of the alloys tested in example 8.

[0216] Figure 50 shows a metallographic analysis image of a prior art cast iron (standard alloy 600 / 3), highlighting the distribution of nodules in the nodular cast iron.

[0217] Figure 51 shows a metallographic analysis image of a cast iron of the present invention (alloy comprising niobium nanoparticles), highlighting the improved distribution of nodules in the nodular cast iron with niobium nanoparticles.

[0218] Based on the images mentioned above, it is possible to observe an improvement in the number of nodules, i.e., 157 nodules / mm². 2 for 219 nodules / mm 2(central region). Additionally, it is possible to observe a substantially more uniform dispersion of the nodules throughout the nodular cast iron matrix and, furthermore, a substantially more uniform distribution of the nodule sizes.

[0219] Without wishing to be bound by theory, it is understood that the substantially more uniform distribution (dispersion of nodules and distribution of their sizes) contributes to the increases in the mechanical properties tested.

[0220] Those skilled in the art will appreciate the knowledge presented here and will be able to reproduce the invention in the forms presented and in other variants and alternatives covered by the scope of the claims.

Claims

Claims 1. Wheel hub for land vehicles characterized by comprising a cylindrical body provided with a flange (3) on its outer diameter, wherein a first end of the cylindrical body is provided with a plurality of ribs (1) arranged around its outer wall, each rib (1) being spaced from the next rib (1) by a recess (2), each rib (1) being equidistant from the adjacent ribs (1), such that each rib (1) and each recess (2) extend axially from the first end of the wheel hub to a convex region (5.1) of the wheel hub, where the outer diameter of the cylindrical body progresses until it reaches the flange (3).

2. Wheel hub, according to claim 1, characterized in that each rib (1) comprises, at the first end, a tubular portion (1.1) provided with a threaded hole for receiving a spindle and comprises a concave portion (1.2) between the tubular portion (1.1) and the convex transition region to the flange (3).

3. Wheel hub, according to claim 1, characterized by comprising a second end of the cylindrical body extending to a second convex region (5.2), where the outer diameter of the cylindrical body progresses until it reaches the flange (3), on a face of the flange (3) opposite to the face where the first convex region is located.

4. Wheel hub, according to claim 1, characterized in that the flange (3) has a plurality of rounded tabs on its outer diameter, each tab having a through hole (4) and spaced by a valley (4.1), such that the distance between diametrically opposite valleys (4.1) is less than the distance between diametrically opposite through holes (4).

5. Wheel hub, according to claim 3, characterized in that at least one of the first convex region (5.1) and the second convex region (5.2) comprises structural reinforcement protrusions (5).

6. Wheel hub, according to claim 1, characterized by being made of a cast iron alloy comprising a mass amount of Niobium nanoparticles.

7. Manufacturing process for a wheel hub for land vehicles characterized by comprising at least the following steps: a. preparation of a casting mold with geometry intended to produce a wheel hub having a flange (3) on its outer diameter, wherein a first end of the cylindrical body is provided with a plurality of ribs (1) arranged around its outer wall, each rib (1) being spaced from the next rib (1) by a recess (2), all ribs (1) being equidistant from each other, so that each rib (1) and each recess (2) extend axially from the first end of the wheel hub to a convex region (5.1) of the wheel hub, where the outer diameter of the cylindrical body progresses until it reaches the flange (3); b. preparation of a metallic alloy formed by iron and a mass quantity of a predefined binding material; c. melting of the metal alloy and filling of the mold with the molten alloy; and d.removal of the part from the mold with the desired geometric characteristics.

8. Process, according to claim 7, characterized by comprising at least one step of modulating the mechanical properties of a metallic material from which the wheel hub is manufactured, by incorporating a mass quantity of Niobium nanoparticles, wherein said mass quantity of Niobium nanoparticles comprises a degree of amortization of at least 19%.

9. Process according to claim 7, characterized by comprising the production steps of a metal wheel hub having geometric characteristics as defined in any one of claims 1 to 6.

10. Vehicle drive axle characterized by comprising at least one wheel hub at at least one end of the drive axle, said wheel hub being as defined in any one of claims 1 to 6.

Images