Method for Determining Sample Quantity in Accurate Testing of Impact Toughness of Diamond Abrasives

Abstract

The present invention relates to a method for determining sample size in a precise diamond abrasive impact toughness test, and belongs to the technical field of diamond abrasive impact toughness testing. Application of the present invention's method can determine the basic number of particles required for testing accuracy, thereby avoiding misjudgment of diamond abrasive performance due to inaccurate impact toughness testing, as well as disputes or conflicts between manufacturers and users, or substandard quality in cutting tools, which can affect the performance of the cutting tools. Application of the present invention can also avoid the economic costs of using an excessive number of particles, such as increased test samples, testing time, and equipment wear.

Description

Technical Field

[0001] The invention belongs to the technical field of diamond abrasive impact toughness testing, and in particular relates to a method for determining a sample amount in a precise test of diamond abrasive impact toughness. Background Art

[0002] Impact toughness is a key technical indicator of diamond abrasive performance, used to indicate its performance level. Diamond abrasives are the hardest abrasives and are primarily used in cutting and grinding machine tools and cutting and grinding tools. Diamond abrasives are the core element of the cutting and grinding capabilities of these tools. Because impact toughness is a core performance indicator of diamond abrasives, only accurate testing of diamond abrasive impact toughness can accurately reflect the actual performance level of diamond abrasives.

[0003] The accuracy of diamond abrasive impact toughness testing is closely related not only to the scientific nature of the test method, the precision of the test equipment, the effectiveness of the test device, and the standardization of the test environment, but also to the method of sampling the test specimen. If not paid attention to, the test error caused by the sample size alone can be greater than the sum of all other errors.

[0004] Diamond abrasives are composed of particles, which are the carriers of the impact toughness properties of diamond abrasives. It is difficult for diamond abrasives to form consistency in shape and quality during the crystallization process of production, resulting in differences in performance between diamond particles. The shapes of diamond abrasives produced in the same batch mainly include hexahedron, octahedron, hexadecahedron, rhombic dodecahedron, octahedron and cube aggregates, convex hexahedron, convex octahedron, convex hexadecahedron, convex rhombic dodecahedron, convex cube and curved surface and aggregates thereof, irregular hexahedron, irregular octahedron, etc. There are about ten typical shapes, see Figure 1 In addition to differences in shape, diamond particles from the same batch can also vary in crystal quality and crystal plumpness. Due to these various inhomogeneities within a single batch of diamond abrasive particles, varying sampling sizes can lead to varying test results. Therefore, a scientific sampling method is crucial for accurate test results that accurately reflect the true impact toughness performance of diamond abrasive products.

[0005] The classic sampling method for diamond abrasive impact toughness test samples is to take a sample of the same weight for testing, regardless of the sample size. The advantage of this sampling method is that the weighing error caused by weighing the sample on a balance is the same for samples of various sizes. However, the error caused by the difference in uniformity between samples of the same sampling weight of different sizes can be more than ten times, or even dozens of times, the weighing error, which is particularly prominent on large-sized samples. For example, if the balance accuracy is 0.0005 grams and the sample weight is 0.2 grams, the weighing error of the balance is only 0.25%, while the range (maximum deviation minus minimum deviation) caused by the unevenness of the 0.2 gram sample may be 3% or 10%. The error caused by the sampling weight is dozens of times the weighing error, and the smaller the sampling weight, the greater the error.

[0006] This is like there are 10 apples in a basket with decreasing weights, and the weight of each apple is different. Now we need to calculate the average value of the apples. If we randomly take out 5 apples from the basket each time and call them one portion to calculate the average value of the total weight of 10 apples, we will hardly measure the same average value (restart each time), and the average values of each portion will vary greatly. If we put 10 portions (100) of 10 such apples in a basket and take out 10 apples at a time, we may get the average value of 10 apples or something close to the average value of 10 apples; if we take 20 apples at a time, there is a greater probability of getting an average value closer to 10 apples; if we take 30 apples at a time, the result will be closer to the average value, or the discreteness of each result will be very small. The shape of each particle of diamond abrasive is almost not exactly the same (strictly speaking), just like Figure 1 As shown, it seems that no two diamond samples in this tray are exactly the same in shape or weight. The differences in sample shape or weight can be compared to the differences in weight of apples. The impact of each deformed diamond crystal on the test results is primarily due to the differences in impact toughness values between these deformed crystals. The extent of this difference is influenced by the magnetic selection (removal of crystals containing metallic impurities) and grading process used in the diamond abrasive. Mainstream production processes ensure that the variability in impact toughness values between test samples is minimized after magnetic and grading selection. Clearly, even after magnetic and grading, testing a single large or medium-sized sample cannot guarantee the required test accuracy, nor can it produce a representative impact toughness value for the entire production batch of diamond abrasives. Since the impact toughness value of the diamond abrasive is inherent in these abrasive grains, improper diamond sampling methods will prevent the extraction of a diamond abrasive sample with representative impact toughness values.

[0007] The differences in sampling and test results are illustrated by the test results of the same real diamond abrasive using different sampling methods. Using a D601 sample, four identical samples of 0.1 gram, 0.2 gram, and 0.4 gram were tested. The range and standard deviation of the 0.1 gram sample were 10.5% and 4.5%, respectively (see Table 1), the range and standard deviation of the 0.2 gram sample were 4.9% and 2.14%, respectively (see Table 2), and the range and standard deviation of the 0.4 gram sample were 3.0% and 1.28%, respectively (see Table 3). The test results show that the smaller the sample size, the greater the range and standard deviation of the test results. The sample test results are highly dispersed (for example, with a 0.1 gram sample), and the test results are highly random, indicating a state of significant uncertainty. Therefore, the sampling method has a significant impact on the accuracy of the test results and may render the test results unusable.

[0008] Table 1 Four parallel tests of the unbroken rate of 0.1g sample of size D601

[0009]

[0010] Table 2 Four parallel tests of the unbroken rate of 0.2g sample of size D601

[0011]

[0012] Table 3 Four parallel tests of the unbroken rate of 0.4g sample of size D601

[0013]

[0014] Summary of the Invention

[0015] (1) Technical issues to be resolved

[0016] The technical problem addressed by this invention is to resolve the significant testing error caused by the current single-portion sampling method for diamond abrasive testing. By using a scientific sampling method, a sample portion is determined that provides comprehensive statistical representation of diamond abrasive properties and minimizes performance dispersion. This improves the accuracy of diamond abrasive impact toughness testing and ensures that the performance results from diamond abrasive testing more accurately reflect the performance level of the diamond abrasive. Furthermore, the diamond abrasive sampling method addresses not only the balance's weighing error but also the more significant sampling error.

[0017] (2) Technical solution

[0018] In order to solve the above technical problems, the present invention provides a method for determining the sample size in the precise test of diamond abrasive impact toughness, comprising the following steps:

[0019] S1. The sample is obtained through size screening, magnetic selection and grade selection in the production process, that is, through "three-stage selection" and used as the test sample;

[0020] S2. Diamond abrasives are divided into three categories according to their shape: the first category includes hexahedrons, octahedrons and hexaoctahedrons, which are called Class I shapes; the second category includes irregular hexahedrons, irregular octahedrons and irregular hexaoctahedrons, which are called Class II shapes; the third category is called Class III shapes, which includes other shapes that do not belong to the first and second categories, so that these three categories of shapes fully cover all the particle shapes of diamond abrasives;

[0021] S3. The shape deformation of the hexahedron includes single-side deformation, two-side deformation, three-side deformation, four-side deformation, five-side deformation and six-side deformation. There are 6 main types of single-side deformation, 15 main types of two-side deformation, 16 main types of three-side deformation, 16 main types of four-side deformation, 6 main types of five-side deformation, and 1 type of six-side deformation. There are 60 types of all deformations in total. Similarly, there are more than 100 types of octahedral deformation and more than 100 types of hexahedral deformation. Let the number of different shapes of particles of type I be N I , the number of particle types of type II is N II , the number of particle types of type III is N III The number of particles of the three types of particle shapes conforms to the relationship of formula (1), and the total number of deformation types of the three types of crystal particles N C , calculated according to formula (2):

[0022] N I ≈N II ≈N III ≈300 (1)

[0023] N C ≈N I +N II +N III ≈3N I ≈900 (2)

[0024] S4. Considering that the crystal is a three-dimensional shape, the symmetrical deformation can be regarded as the same, and different deformation types will be assimilated by the symmetry dimension 3. Therefore, the number of heteromorphic species of diamond particles is N. D Calculate according to formula (3):

[0025]

[0026] S5. The deformation difference of each deformed crystal is graded according to the degree of influence on the impact toughness; the impact toughness value difference range between the same-shaped particles in the same grade of diamond is RD , let the level difference interval be I L , the impact toughness difference between particles of the same shape is divided into L N The number of impact levels is related to the uniformity level of the "three-stage sorting" or the maximum range of a single test of the sample after the "three-stage sorting". Different particles with slight changes in each grade are regarded as particles of the same shape in the impact level.

[0027] S6. The total number of particles of different shapes and different impact levels is N DL Calculate according to formula (4); combine the particles of different shapes and the same impact toughness value composed of the number of particles of type I, type II and type III to obtain the equivalent number N E Calculate according to formula (5):

[0028] N DL =N D ×L N (4)

[0029]

[0030] S7. For the coarsest diamond abrasive, let the total number of particles in the total test sample of this size be N T , by using the sample particle magnification M to the equivalent number N E The equivalent number is magnified and calculated according to formula (6), where M is an integer not less than 2;

[0031] N T =M×N E (6)

[0032] S8. Multiply the number of particles in the next size sample by the particle increment coefficient β to increase the number of abrasive particles. Let the ordinal number of the sample from large to small be n. The ordinal number n corresponding to large and medium size grades is shown in the following table:

[0033] Correspondence table between size brand and ordinal number n

[0034] Size brand D851 D711 D601 D501 D426 D356 D301 n 1 2 3 4 5 6 7

[0035] S9. Let the number of particles in diamond samples of different sizes be N. Tn , calculated according to formula (7), where n is the serial number representing different sizes, and N in formula (7) Tn-1 Yes N Tn The number of test particles of the previous particle size, β n is the particle increment coefficient corresponding to the size of the ordinal number n, the particle increment coefficient β n The value depends on the level of the "three-stage selection" process used;

[0036] N Tn =N Tn-1 ×β n (7)

[0037] When the particle increment coefficient β of each size of diamond abrasive is the same, the number of particles N that the diamond sample should have is Tn Calculate according to formula (8), N in formula (8) T1 is the total number of particles required for a specimen of size D851;

[0038] N Tn =N T1 ×β n-1 (8)

[0039] S10. For large and medium-sized diamond abrasives of D851, D711, D601, D501, D426, D356, and D301, perform steps S11 and S12 to calculate the number of representative particles and the number of copies; for abrasives with fine diamond particles smaller than D301, use one sample to represent the impact toughness value of the diamond;

[0040] S11. According to physical statistics, the number of particles contained in 0.4g and 1 carat weight of diamond abrasives of large and medium sizes D851, D711, D601, D501, D426, D356, and D301 is G. n , see the table below:

[0041] Table of the number of particles contained in a 0.4g sample of large and medium-sized diamond abrasives

[0042]

[0043]

[0044] S12. The maximum weight of diamond abrasive that can be loaded into the impact tube at one time during each impact toughness test of the sample is 0.4 grams. When the weight corresponding to the number of diamond particles of certain size exceeds multiples of 0.4 grams and there is an excess part less than 0.4 grams, the sample weight shall be divided into 0.4 gram portions, and the portion less than 0.4 grams shall be rounded up to 0.4 grams as one portion. The impact toughness test of the sample is based on the number of test portions P n Arrange the test, P n is an integer, the number of copies P n Calculate according to formula (9), the symbol in formula (9) is It is the rounding up operator, that is, the excess decimal part after rounding to an integer is counted as 1;

[0045]

[0046] The present invention also provides a system for implementing the method.

[0047] The invention also provides a diamond abrasive impact toughness testing method using the method.

[0048] (3) Beneficial effects

[0049] The inventors of the present invention discovered a pattern in which the range and standard deviation of diamond impact toughness values decrease as the number of diamond sample particles increases. Based on this, they analyzed the number of types of typical diamond shape deformations and used technical elements such as particle shape assimilation, equal value merging, impact toughness value grading, magnification factor, and particle size increment factor to support the calculation of a reasonable number of particles in the sample. They established a set of algorithms for the basic number of particles required for accurately testing the diamond impact toughness value.

[0050] The diamond impact toughness value test using the sample weight determined by the method of the present invention is 3 to 4 times or more higher in accuracy than the traditional method of using a 0.4 gram sample for testing regardless of particle size. This effect has been verified to be reliable and authentic through many tests.

[0051] The method of the present invention can be used to determine the basic number of particles required for testing accuracy, thereby avoiding misjudgment of diamond abrasive performance due to inaccurate impact toughness testing, which can lead to disputes or conflicts between manufacturers and users, or substandard quality in cutting tools, affecting the performance of the cutting tools. The application of the present invention can also avoid the economic costs of using an excessive number of particles, such as test specimens, testing time, and equipment wear. BRIEF DESCRIPTION OF THE DRAWINGS

[0052] Figure 1 is the shape diagram of diamond superabrasive particles;

[0053] Figure 2 This is a graph showing the relationship between the range / standard deviation of diamond impact toughness and the number of particles. DETAILED DESCRIPTION

[0054] In order to make the purpose, content and advantages of the present invention more clear, the specific implementation methods of the present invention are further described in detail below with reference to the accompanying drawings and examples.

[0055] The inventors of the present invention have found through a large amount of test data that the range and standard deviation of the diamond impact toughness value test have a rule of decreasing with the increase of the number of particles. Figure 2 As shown, by finding the basic number of diamond particles representing the impact toughness value, accurate testing of the diamond impact toughness value can be achieved.

[0056] Based on the above findings, the design idea of the present invention is: to classify the diamond abrasive particles, assimilate the symmetry of the shape dimensions, and merge the different shapes to count the number of particle shapes, and then determine the number of different particle groups according to the difference in impact toughness of the shape particles, and then use the amplification factor to act on the number of different particle groups to reduce the discreteness of the impact toughness value test of the sample diamond abrasive. In addition, in response to the phenomenon of reduced uniformity of the "three-part selection" of large, medium and lower sizes of diamond abrasives, the lower size particle increment coefficient is used to act on the number of representative particles of the upper size to obtain the basic particle number of the diamond abrasive with a high probability of taking a representative sample, and the sample sampling plan is calculated according to the basic particle number according to the test requirements of the whole sample for testing, thereby achieving accurate testing of the diamond impact toughness value. The specific test portion determination method of the present invention includes the following steps:

[0057] S1. The samples obtained through size screening, magnetic selection and grade selection in the production process (referred to as "three-stage selection") are used as test samples to meet the basic conditions required for sample factory inspection and testing.

[0058] S2. Diamond abrasives are divided into three categories based on their shapes: the first category is hexahedrons (cubes), octahedrons, and hexadecahedrons, referred to as Class I; the second category is irregular hexahedrons, irregular octahedrons, and irregular hexadecahedrons, referred to as Class II; the third category is rhombic dodecahedrons, polyhedrons, and other shapes, referred to as Class III. The third category includes other shapes that do not belong to Class I and Class II. These three categories of shapes fully cover all diamond abrasive particle shapes.

[0059] S3. The shape deformation of the hexahedron includes single-side deformation, two-side deformation, three-side deformation, four-side deformation, five-side deformation and six-side deformation. There are 6 main types of single-side deformation, 15 main types of two-side deformation, 16 main types of three-side deformation, 16 main types of four-side deformation, 6 main types of five-side deformation, and 1 type of six-side deformation. The total number of all deformations is 60. Similarly, there are more than 100 types of octahedral deformation and more than 100 types of hexadecahedral deformation. Let the number of different shapes of particles of type I be N I (For example, 300 types), the number of particle types of type II is N II , the number of particle types of type III is N III The statistical weight of the three types of shapes in production is close to 1 / 3. Since the diamonds in the sample are selected by grade, the average weight of particles of each type of shape is close to the same. Therefore, the number of particles of the three types of particle shapes conforms to the relationship of formula (1). The total number of deformation types of the three types of crystal particles N C , calculated according to formula (2).

[0060] N I ≈N II ≈N III ≈300 (1)

[0061] N C ≈N I +N II +N III ≈3N I ≈900 (2)

[0062] S4. Considering that the crystal is a three-dimensional shape, the symmetrical deformation can be regarded as the same, and different deformation types will be assimilated by the symmetry dimension 3. Therefore, the number of heteromorphic species of diamond particles is N. D , calculated according to formula (3) (for example, 300 types).

[0063]

[0064] S5. The deformation difference of each deformed crystal is classified according to the degree of influence on the impact toughness. Assume that the impact toughness value difference range between the same-shaped particles in the same grade of diamond is R D (After “three-stage selection” samples, R D 0~10%), set the step interval to I L (For example, I L =0.5%), the impact toughness difference between particles of the same shape is divided into L N The number of impact levels is related to the uniformity level of the "three-stage sorting" or the maximum range of a single test of the sample after the "three-stage sorting" (for example, a single test range of 3% to 5% is divided into 6 to 10 impact levels). Different particles with slight variations within each level can be regarded as particles of the same shape in that impact level.

[0065] S6. The total number of particles of different shapes and different impact levels is N DL , calculated according to formula (4). The particles of different shapes and the same impact toughness value composed of the number of particles of type I, type II and type III are merged into an equal value to obtain the equal value number N E (i.e. the number of particles with different particle shapes but the same impact toughness value), calculated according to formula (5).

[0066] N DL =N D ×L N (4)

[0067]

[0068] S7. For the coarsest diamond abrasive (e.g. D851), let the total number of particles in the total test sample of this size be NT , by using the sample particle magnification M to the equivalent number N E The equivalent number is amplified and calculated according to formula (6). M is an integer not less than 2 and can be any integer such as 2, 3, 4, ..., 10. The larger M is, the smaller the dispersion of the impact toughness values of the specimens tested. However, a large M will increase the cost and time of the test (usually M can be taken as 3).

[0069] N T =M×N E (6)

[0070] S8. The uniformity of diamond abrasives in "three-stage sorting" decreases as the abrasive size decreases (i.e., decreasing abrasive size reduces the purity of "three-stage sorting"). To ensure that the dispersion of impact toughness values for specimens of the same grade across different sizes is approximately equal, the number of particles in the next-largest specimen size should be multiplied by the particle increment factor β to increase the number of abrasive particles, so that the dispersion of impact toughness values for the upper and lower sizes is similar. Let n be the ordinal number of the specimens from largest to smallest. The ordinal number n corresponding to large and medium-sized grades is shown in Table 4.

[0071] Table 4 Correspondence between size brand and ordinal number n

[0072] Size brand D851 D711 D601 D501 D426 D356 D301 n 1 2 3 4 5 6 7

[0073] S9. Let the number of particles in diamond samples of different sizes be N. Tn , calculated according to formula (7), where n is a serial number representing different sizes. Tn-1 Yes N Tn The number of test particles of the previous particle size, β n Is the particle increment coefficient of the size corresponding to the size ordinal number n. Particle increment coefficient β n The value depends on the level of the "three-stage selection" process used, β n =1.1~1.5, the higher the process level of “three-stage selection”, the higher the β n The smaller.

[0074] N Tn =N Tn-1 ×β n (7)

[0075] When the particle increment coefficient β of each size of diamond abrasive is the same, the number of particles N that the diamond sample should have is Tn Calculate according to formula (8). N in formula (8) T1 is the total number of particles required for a specimen of size D851.

[0076] N Tn =N T1 ×βn-1 (8)

[0077] S10. For large and medium-sized diamond abrasives of D851, D711, D601, D501, D426, D356, and D301, execute steps S11 and S12 to calculate the number of representative particles and the number of portions. For abrasives with fine diamond particles smaller than D301 (e.g., D251, D213, and below), since the number of particles contained in a 0.4 gram weight is usually very large, multiple samples are not required to ensure the necessary number of particles. Only one sample is required to represent the impact toughness value of the diamond. Therefore, diamond abrasives of these sizes do not need to calculate the number of representative particles and the number of portions.

[0078] S11. According to physical statistics, the number of particles contained in 0.4g and 1 carat weight of diamond abrasives of large and medium sizes D851, D711, D601, D501, D426, D356, and D301 is G. n , as shown in Table 5.

[0079] Table 5 Number of particles in a 0.4g sample of large and medium-sized diamond abrasives

[0080] Size and brand D851 D711 D601 D501 D426 D356 D301 <![CDATA[G n ]]> <![CDATA[G1]]> <![CDATA[G2]]> <![CDATA[G3]]> <![CDATA[G4]]> <![CDATA[G5]]> <![CDATA[G6]]> <![CDATA[G7]]> 0.4 g sample 396 pieces 668 pieces 1120 pieces 1808 2944 4388 pieces 7618 1 carat (0.2 g) 198 pieces 334 pieces 560 pieces 904 1472 2194 3809 pieces

[0081] S12. The maximum weight of diamond abrasive that can be loaded into the impact tube at one time during each impact toughness test of the sample is 0.4 grams. When the weight corresponding to the number of diamond particles of a certain size exceeds multiples of 0.4 grams and there is an excess part less than 0.4 grams, the sample weight needs to be divided into 0.4 gram portions, and the remaining part less than 0.4 grams is rounded up to 0.4 grams as one portion. The impact toughness test of the sample is based on the number of test portions P n Arrange the test, P n is an integer, and the number of copies Pn is calculated according to formula (9). The symbols in formula (9) are It is the rounding up operator, that is, the excess decimal part after rounding to an integer is counted as 1.

[0082]

[0083] The method of the present invention was tested and verified using actual diamond abrasive D711, and the results were very good. The specific contents of the verification of the method of the present invention on diamond abrasive D711 are as follows:

[0084] 1) First, the total number of particles N required for the maximum size of the D851 sample is obtained. T1 After the “three-stage selection” of diamond abrasives, the difference in impact toughness value allowed in a single test is 5%. The difference in impact toughness value between particles of the same shape is divided into 10 levels, namely L N=10, because the number of diamond particle heteromorphs is N D = 300, the total number of particles of different shapes and levels is N DL =N D ×L N =300×10=3000, the equivalent number of particles after equal value merging N E =N DL ÷3=1000, using the sample particle magnification M=4 times the equivalent value number N E Perform equal amount amplification to obtain the total number of particles N in the D851 sample. T =M×N E =4×1000=4000.

[0085] 2) The ordinal number of D711 is n = 2. The particle increment coefficient of the corresponding size is 1.2. The number of particles that a D711 size diamond sample should have is N. T2 =N T1 ×β n =4000×1.2=4800.

[0086] 3) The number of particles contained in 0.4 g of D711 sample is G2 = 668. The total number of particles required for the D711 sample is N T2 Calculate the number of test samples share.

[0087] 4) Eight 0.4 g D711 specimens were tested for impact toughness. The test data are shown in Table 6. The range of the test results is 5.0%, the average is 72.5%, and the standard deviation is 1.4%.

[0088] Table 6 Unbroken rate test of 8 0.4g samples of size D711

[0089]

[0090]

[0091] It can be seen from the test data that if the D711 impact toughness value is tested using only a 0.4 gram sample according to the current traditional sampling amount, the test result will be 75.2% or 70.2%, and the maximum difference between them can reach 5.0%. However, the impact toughness value obtained by testing 8 samples is 72.5%, and its standard deviation is only 1.4%, which is less than the limit of 1.5%. The test accuracy is only about one-fourth (0.28) of the test accuracy of a 0.4 gram sample. Therefore, the number of diamond abrasive particles calculated by the method of the present invention can accurately obtain the sample size required for the test accuracy, while also avoiding the waste of time, abrasive and equipment caused by blindly increasing the number for accuracy.

[0092] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the technical principles of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A method for determining the sample size in a precise test of diamond abrasive impact toughness, characterized in that: The following steps are involved: S1. Obtain samples through size screening, magnetic selection and grade selection during the production process, that is, through "three-stage selection" to obtain samples, and use them as test samples; S2. Diamond abrasives are divided into three categories according to their shape: the first category includes hexahedrons, octahedrons and hexaoctahedrons, which are called Class I shapes; the second category includes irregular hexahedrons, irregular octahedrons and irregular hexaoctahedrons, which are called Class II shapes; the third category is called Class III shapes, which includes other shapes that do not belong to the first and second categories, so that these three categories of shapes fully cover all the particle shapes of diamond abrasives; S3. The shape deformation of the hexahedron includes single-side deformation, two-side deformation, three-side deformation, four-side deformation, five-side deformation and six-side deformation. There are 6 main types of single-side deformation, 15 main types of two-side deformation, 16 main types of three-side deformation, 16 main types of four-side deformation, 6 main types of five-side deformation, and 1 type of six-side deformation. There are 60 types of deformation in total. Similarly, there are more than 100 types of octahedral deformation and more than 100 types of hexahedral deformation. Let the number of different shapes of particles of type I be N Ⅰ , the number of particle types of type II is N Ⅱ , the number of particle types of type III is N Ⅲ The number of particles of the three types of particle shapes conforms to the relationship of formula (1), and the total number of deformation types of the three types of crystal particles N C , calculated according to formula (2): N Ⅰ ≈N Ⅱ ≈N Ⅲ ≈300 (1) N C ≈N Ⅰ +N Ⅱ +N Ⅲ ≈3N Ⅰ ≈900 (2) S4. Considering that the crystal is a three-dimensional shape, the symmetrical deformation can be regarded as the same, and different deformation types will be assimilated by the symmetry dimension 3. Therefore, the number of heteromorphic species of diamond particles is N. D Calculate according to formula (3): S5. The deformation difference of each deformed crystal is graded according to the degree of influence on the impact toughness; the impact toughness value difference range between the same-shaped particles in the same grade of diamond is R D , let the level difference interval be I L , the impact toughness difference between particles of the same shape is divided into L N The number of impact grades is related to the uniformity level of "three-stage sorting" or the maximum range of a single test of the sample after "three-stage sorting". Different particles with slight changes in each grade are regarded as particles of the same shape in the impact grade; S6. The total number of particles of different shapes and different impact levels is N DL Calculate according to formula (4); combine the particles of different shapes and the same impact toughness value composed of the number of particles of type I, type II and type III to obtain the equivalent number N E Calculate according to formula (5): N DL =N D ×L N (4) S7. For the coarsest diamond abrasive, let the total number of particles in the total test sample of this size be N T , by using the sample particle magnification M to the equivalent number N E The equivalent number is amplified and calculated according to formula (6), where M is an integer not less than 2; N T =M×N E (6) S8. Multiply the number of particles in the next size sample by the particle increment coefficient β to increase the number of abrasive particles. Let the ordinal number of the sample from large to small be n. The ordinal number n corresponding to large and medium size grades is shown in the following table: Correspondence table between size brand and ordinal number n S9. Let the number of particles in diamond samples of different sizes be N. Tn , calculated according to formula (7), where n is the serial number representing different sizes, and N in formula (7) Tn-1 Yes N Tn The number of test particles of the previous particle size, β n is the particle increment coefficient corresponding to the size of the ordinal number n, the particle increment coefficient β n The value depends on the level of "three-stage selection" process adopted; N Tn =N Tn-1 ×β n (7) When the particle increment coefficient β of each size of diamond abrasive is the same, the number of particles N that the diamond sample should have is Tn Calculate according to formula (8), N in formula (8) T1 is the total number of particles required for a specimen of size D851; N Tn =N T1 ×β n-1 (8) S10. For large and medium-sized diamond abrasives of D851, D711, D601, D501, D426, D356, and D301, perform steps S11 and S12 to calculate the number of representative particles and the number of copies; for abrasives with fine diamond particles smaller than D301, use one sample to represent the impact toughness value of the diamond; S11. According to physical statistics, the number of particles contained in 0.4g and 1 carat weight of diamond abrasives of large and medium sizes D851, D711, D601, D501, D426, D356, and D301 is G. n , see the table below: Table of the number of particles contained in a 0.4g sample of large and medium-sized diamond abrasives S12. The maximum weight of diamond abrasive that can be loaded into the impact tube at one time during each impact toughness test of the sample is 0.4 grams. When the weight corresponding to the number of diamond particles of certain size exceeds multiples of 0.4 grams and there is an excess part less than 0.4 grams, the sample weight shall be divided into 0.4 gram portions, and the portion less than 0.4 grams shall be rounded up to 0.4 grams as one portion. The impact toughness test of the sample is based on the number of test portions P n Arrange the test, P n is an integer, the number of copies P n Calculate according to formula (9), the symbol in formula (9) It is the rounding up operator, that is, the excess decimal part after rounding to an integer is counted as 1; 2. The method according to claim 1, wherein The third category includes rhombic dodecahedrons and polyhedrons.

3. The method according to claim 1, wherein R D 0 to 10%.

4. The method according to claim 1, wherein I L ＝0.5％。 5. The method according to claim 1, wherein The single test range is 3% to 5%, which is divided into 6 to 10 impact levels.

6. The method according to claim 1, wherein M is taken as 3.

7. The method according to claim 1, wherein β n ＝1.1～1.5。 8. The method according to claim 7, wherein The higher the level of "three-stage selection" technology, the higher the β n The smaller.

9. A system for implementing the method according to any one of claims 1 to 8.

10. A method for testing the impact toughness of diamond abrasives using the method according to any one of claims 1 to 8.

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