METHOD FOR DESIGNING GRINDING DISC FOR HIGH-WEAR-RESISTANT WORKPIECES

Abstract

A method for designing a grinding disc for workpieces includes the following steps: determining process dimension parameters of a grinding process, and the process dimension parameters of the grinding process comprising a rotational speed ωm of the grinding disc and a rotational speed ωw of a workpiece or a rotational speed ωs of a sun wheel, a radius r of the workpiece, a radius R of the grinding disc, and an eccentric distance e; dividing the grinding disc is into regions; calculating trajectory densities of a point Pi on the workpiece relative to the different divided regions of the grinding disc; calculating areas of the different divided regions in proportion based on the trajectory densities on the different divided regions to obtain a grinding disc pattern; and obtaining a patterned grinding disc through machining or by arranging hot-pressed sintered blocks per unit area according to the grinding disc pattern.

Description

FIELD OF THE DISCLOSURE

The present disclosure relates to the field of ultra-precision machining technology, specifically to a method for designing a grinding disc for high wear-resistant workpieces.

BACKGROUND OF THE DISCLOSURE

Materials such as silicon carbide (SiC), diamond, and gallium nitride (GaN) possess excellent physical properties, including a wide bandgap, high thermal conductivity, good thermal stability, and high saturation drift velocity. These properties make them widely applicable in fields such as high frequency, high temperature, radiation resistance, and optoelectronics. The industrial applications of these materials demand extremely high surface quality. However, their extremely high hardness and chemical inertness confer high wear resistance, making them difficult to machine. These characteristics have hindered their widespread use in industrial applications.

Grinding, as a key method of precision and ultra-precision machining, can achieve excellent surface quality and is therefore widely used in processing semiconductor substrates. During the end-face grinding of high-wear-resistant workpieces, the grinding disc inevitably wears down, leading to a decrease in flatness. Errors on the grinding disc surface are transmitted to the workpiece surface during processing, negatively impacting the precision of the workpiece surface. When the flatness error exceeds the allowable range, the grinding disc must be dressed, which not only reduces the service life of the grinding disc but also lowers production efficiency.

BRIEF SUMMARY OF THE DISCLOSURE

The technical problem to be solved by the present disclosure is to provide an

The purpose of the present disclosure is to provide a method for designing a grinding disc for high-wear-resistant workpieces. This method calculates areas of regions based on a trajectory density distribution on the grinding disc, thereby addressing issues of low processing efficiency, uneven wear of the grinding disc, and significant surface profile errors in the workpieces associated with existing high-wear-resistant workpiece processing techniques.

In order to solve the above technical problems, the present disclosure provides a method for designing a grinding disc for high-wear-resistant workpieces comprising the following steps:

• • (1) determining process dimension parameters of a grinding process, and the process dimension parameters of the grinding process comprising a rotational speed ω_m of a grinding disc and a rotational speed ω_w of a workpiece or a rotational speed ω_s of a sun wheel, a radius r of the workpiece, a radius R of the grinding disc, and an eccentric distance e;
  • (2) dividing the grinding disc is into different divided regions;
  • (3) calculating trajectory densities of a point P_i on the workpiece relative to the different divided regions of the grinding disc;
  • (4) calculating areas of the different divided regions in proportion based on the trajectory densities on the different divided regions to obtain a grinding disc pattern; and
  • (5) obtaining a patterned grinding disc through machining or by arranging hot-pressed sintered blocks per unit area according to the grinding disc pattern.

When the grinding disc is divided into the different divided regions, the different divided regions are concentric rings with a center of the grinding disc as an origin, or the different divided regions are rectangles arranged in an array with equal areas.

An actual area of each of the different divided regions of the grinding disc is calculated according to a formula

$A_u=A_b\frac{{\rho }_u}{{\rho }_{\max }}\left(u=1,2,\dots ,M\right),$

wherein the A_b is an area base value, the A_b is not greater than an area of a region of the different divided regions with a maximum track density, the ρ_max is the maximum track density among the different divided regions, and the Pu is a trajectory density on a corresponding one of the different divided regions.

The step 3 comprises dividing a surface of the workpiece into grids with a spacing of 1 mm, calculating trajectory lengths of all of the grids of the workpiece on the different divided regions of the according to a formula grinding disc l_iu,t=√{square root over ([x_i(t+t_p)−x_i(t)]²+[y_i(t+t_p)−y_i(t)]²)}, wherein the (x_i, y_i) is a coordinate of the point P_i, and the t_p is a time step, and calculating the trajectory density ρ_u on a corresponding one of the different divided regions.

A base material of the grinding disc obtained through machining is an active metal.

The hot-pressed sintered blocks are made of active metal powder and abrasive grains through a hot-press sintering process.

The present disclosure provides the method for designing the grinding disc for the high-wear-resistant workpieces. The present disclosure performs calculating the trajectory densities in the different divided regions and proportionally determining the areas of the different divided regions based on the trajectory densities of the different divided regions to obtain the grinding disc pattern. The grinding disc pattern is then realized by machining or arranging hot-pressed sintered blocks per unit area to create the patterned grinding disc. The present disclosure quickly generates a grinding disc pattern based on the trajectory densities during face grinding, enabling the design of complex-shaped grinding discs. This method facilitates rapid design and precise production of complex patterns, effectively improving uniformity of grinding disc wear during face grinding, enhancing the surface profile accuracy of the workpieces, reducing grinding time, and increasing processing efficiency.

Compared with the existing techniques, the method for designing the grinding disc for the high-wear-resistant workpieces has the following advantages.

• • 1. The present disclosure effectively resolves an issue of uneven wear on the grinding disc, ensuring uniform wear on a processing area.
  • 2. The present disclosure enables the grinding disc to be obtained through mechanical processing, reducing production difficulty and cost.
  • 3. The present disclosure significantly enhances processing efficiency and surface profile accuracy of the high-wear-resistant workpieces.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 illustrates a flowchart of a method for designing a grinding disc for high-wear-resistant workpieces in an embodiment of the present disclosure.

FIG. 2 illustrates a schematic diagram of single-side grinding processing provided in Embodiment 1 of the present disclosure.

FIG. 3 illustrates a schematic diagram of divided regions of the grinding disc provided in Embodiment 1 of the present disclosure.

FIG. 4 illustrates a grinding disc pattern or single-side grinding provided in Embodiment 1 of the present disclosure.

FIG. 5 illustrates a schematic diagram of double-side grinding processing provided in Embodiment 2 of the present disclosure.

FIG. 6 illustrates a grinding disc pattern for double-side grinding provided in Embodiment 2 of the present disclosure.

DETAILED DESCRIPTION OF THE EMBODIMENTS

In order to further explain the technical solution of the present disclosure, the present disclosure will be described in detail below through specific embodiments.

A method for designing a grinding disc for high-wear-resistant workpieces comprises the following steps.

(1) First, process dimension parameters of a grinding process are determined, and the process dimension parameters of the grinding process comprise a rotational speed ω_m of a grinding disc and a rotational speed ω_w of a workpiece or a rotational speed ω_s of a sun wheel, a radius r of the workpiece, a radius R of the grinding disc, and an eccentric distance e. (2) The grinding disc is divided into different divided regions. (3) Trajectory densities of a point P_i on the workpiece relative to the different divided regions of the grinding disc are calculated. (4) Areas of the different divided regions are calculated in proportion based on the trajectory densities on the different divided regions to obtain a grinding disc pattern. (5) A patterned grinding disc is obtained through machining or by arranging hot-pressed sintered blocks per unit area according to the grinding disc pattern.

When the grinding disc is divided into the different divided regions, the different divided regions can be concentric rings with a center of the grinding disc as an origin, or the different divided regions can be rectangles arranged in an array with equal areas.

An actual area A_u of each of the different divided regions of the grinding disc is calculated according to a formula

$A_u=A_b\frac{{\rho }_u}{{\rho }_{\max }}\left(u=1,2,\dots ,M\right).$

The A_b is an area base value, the A_b is not greater than an area of a region of the different divided regions with a maximum track density, the ρ_max is the maximum track density among the different divided regions, and the Pu is a trajectory density on a corresponding one of the different divided regions.

A base material of the grinding disc obtained through machining is an active metal.

The hot-pressed sintered blocks are made of active metal powder and abrasive grains through a hot-press sintering process.

Embodiment 1

A method for designing a grinding disc for high-wear-resistant workpieces comprises the following steps.

Step 1: process dimension parameters of a single-side grinding process are determined.

The process dimension parameters of the single-side grinding process comprise a rotational speed ω_w of a workpiece, a rotational speed Om of a grinding disc, a radius r of the workpiece, a radius R of the grinding disc, and an eccentric distance e. The rotational speed ω_w of the workpiece is 60 rpm, and the rotational speed Om of the grinding disc is 100 rpm. The radius r of the workpiece is 50 mm, and the radius R of the grinding disc is 360 mm. The eccentric distance e is 90 mm. A schematic diagram of the single-side grinding process is shown in FIG. 2.

Step 2: A surface of the grinding disc is divided into different divided regions.

The grinding disc is divided into concentric rings, and an inner radius and an outer radius of each of the concentric rings differ by 10 mm, as shown in FIG. 3.

Step 3: Trajectory densities relative to the regions of the grinding disc are calculated.

A surface of the workpiece is divided into grids with a spacing of 1 mm. Trajectory lengths of all of the grids of the workpiece on the regions of the grinding disc are calculated according to a formula l_iu,t=√{square root over ([x_i(t+t_p)−x_i(t)]²+[y_i(t+t_p)−y_i(t)]²)}. The (x_i, y_i) is a coordinate of a point P_i, and the t_p is a time step. Then, the trajectory density ρ_u of a corresponding one of the different divided regions is calculated.

Step 4: Areas of the different divided regions are calculated to obtain a grinding disc pattern.

Based on the trajectory densities on the different divided regions, an actual area of each of the different divided regions of the grinding disc are calculated according to a formula

$A_u=A_b\frac{{\rho }_u}{{\rho }_{\max }}\left(u=1,2,\dots ,M\right).$

The A_b is an area base value, and the A_b is set to 3550 mm²

Step 5: a patterned grinding disc is obtained through machining according to the grinding disc pattern, as shown in FIG. 4.

An excess area in the different divided regions of the grinding disc is removed through machining to obtain the patterned grinding disc.

Embodiment 2

A method for designing a grinding disc for high-wear-resistant workpieces comprises the following steps.

Step 1: process dimension parameters of a double-side grinding process are determined.

The process dimension parameters of the double-side grinding process comprises a rotational speed ω_s of a sun wheel, a rotational speed ω_m of a grinding disc, a radius r of a workpiece, a radius R of the grinding disc, and an eccentric distance e. The rotational speed ω_s of the sun wheel is 10 rpm, and the rotational speed Om of the grinding disc is 80 rpm. The radius r of the workpiece is 50 mm, and the radius R of the grinding disc is 150 mm. The eccentric distance e is 58 mm. A schematic diagram of the double-side grinding process is shown in FIG. 5.

Step 2: A surface of the grinding disc is divided into different divided regions.

The grinding disc is divided into concentric rings, and an inner radius and an outer radius of each of the concentric rings differ by 20 mm.

Step 3: Trajectory densities relative to the different divided regions of the grinding disc are calculated.

A surface of the workpiece is divided into grids with a spacing of 1 mm. Trajectory lengths of all of the grids of the workpiece on the different divided regions of the grinding disc are calculated according to a formula l_iu,t=√{square root over ([x_i(t+t_p)−x_i(t)]²+[y_i(t+t_p)−y_i(t)]²)}. The (x_i, y_i) is a coordinate of the point P_i, and the t_p is a time step. Then, the trajectory density ρ_u on a corresponding one of the different divided regions is calculated.

Step 4: Areas of the different divided regions are calculated to obtain a grinding disc pattern.

Based on the trajectory densities on the different divided regions, an actual area of each of the different divided regions of the grinding disc are calculated according to a formula

$A_u=A_b\frac{{\rho }_u}{{\rho }_{\max }}\left(u=1,2,\dots ,M\right).$

The A_b is an area base value, and the A_b is set to 25000 mm²

Step 5: a patterned grinding disc is obtained through machining according to the grinding disc pattern, as shown in FIG. 6.

An excess area in the different divided regions of the grinding disc is removed through machining to obtain the patterned grinding disc.

The above embodiments and drawings do not limit the product form and style of the present disclosure. Any appropriate changes or modifications made by those of ordinary skill in the art shall be regarded as not departing from the patent scope of the present disclosure.

Claims

1. A method for designing a grinding disc comprising the following steps: (1) determining process dimension parameters of a grinding process, and the process dimension parameters of the grinding process comprising a rotational speed ωm of the grinding disc and a rotational speed ωw of a workpiece or a rotational speed ωs of a sun wheel, a radius r of the workpiece, a radius R of the grinding disc, and an eccentric distance e;(2) dividing the grinding disc into different divided regions;(3) calculating trajectory densities of a point Pi on the workpiece relative to the different divided regions of the grinding disc;(4) calculating areas of the different divided regions in proportion based on the trajectory densities on the different divided regions to obtain a grinding disc pattern; and(5) obtaining a patterned grinding disc through machining or by arranging hot-pressed sintered blocks per unit area according to the grinding disc pattern.

2. The method for designing the grinding disc according to claim 1, wherein: when the grinding disc is divided into the different divided regions, the different divided regions are concentric rings with a center of the grinding disc as an origin, or the different divided regions are rectangles arranged in an array with equal areas.

3. The method for designing the grinding disc according to claim 1, wherein: an actual area of each of the different divided regions of the grinding disc is calculated according to a formula

4. The method for designing the grinding disc according to claim 3, wherein the step 3 comprises: dividing a surface of the workpiece into grids with a spacing of 1 mm,calculating trajectory lengths of all of the grids of the workpiece on the different divided regions of the disc grinding according to a formula liu,t=√{square root over ([xi(t+tp)−xi(t)]2+[yi(t+tp)−yi(t)]2)}, wherein the (xi, yi) is a coordinate of the point Pi, and the tp is a time step, andcalculating the trajectory density ρu on the corresponding one of the different divided regions.

5. The method for designing the grinding disc according to claim 1, wherein: a base material of the grinding disc obtained through the machining is an active metal.

6. The method for designing the grinding disc according to claim 1, wherein: the hot-pressed sintered blocks are made of active metal powder and abrasive grains through a hot-press sintering process.