Gradient structure of metallic bond sintered grinding wheel and manufacturing process of gradient structure

Abstract

The invention discloses a gradient structure of a metallic bond sintered grinding wheel and a manufacturing process of the gradient structure, and belongs to the technical field of grinding machining. The grinding wheel is composed of a working layer and a non-working layer, the working layer is of a gradient structure design and comprises at least three gradient layers distributed in the radial direction, the content of metal binders, the grain size of abrasive materials or the types of the abrasive materials of all the gradient layers are changed in a gradient mode, and the content of the metal binders is gradually decreased layer by layer from the outer edge to the inner edge of the grinding wheel. The abrasive particle size increases layer by layer from the outer edge to the inner edge. The manufacturing process comprises the steps of preparing a mixture according to the proportion, carrying out layered centrifugal loading, carrying out stepped heating sintering and carrying out cooling machine processing, laser surface micro-texture processing can also be carried out on the working layer, and rare earth elements are added into the mixture to serve as a sintering aid. By optimizing the structure and the manufacturing process of the grinding wheel, the performance of each part of the grinding wheel is optimized, the grinding efficiency is remarkably improved, the service life is remarkably prolonged, the machining quality is remarkably improved, the production cost is reduced, and the grinding wheel has good application prospects in the field of grinding machining.

Description

Technical Field

[0001] The invention relates to the technical field of metal bond grinding wheels, and in particular to a gradient structure of a metal bond sintered grinding wheel and a manufacturing process thereof. Background Art

[0002] In the field of grinding, metal-bond sintered grinding wheels are widely used for machining hard, brittle, and difficult-to-machine metal materials due to their excellent strength, wear resistance, and grip. However, traditional metal-bond sintered grinding wheels typically utilize a uniform structural design, which presents numerous problems in actual use. For example, the overall performance of the working layer struggles to balance grinding efficiency and service life. The outer edge of the grinding wheel wears rapidly, while the performance of the inner portion cannot be fully utilized. This results in poor overall performance and unstable machining quality, as well as material waste and increased production costs.

[0003] Therefore, how to provide a gradient structure of a metal bond sintered grinding wheel and a manufacturing process thereof to solve the problems existing in the prior art is of great significance to its application. Summary of the Invention

[0004] In view of this, the purpose of this application is to provide a gradient structure of a metal bond sintered grinding wheel and a manufacturing process thereof, so as to solve the problem that the overall performance of the working layer is difficult to balance grinding efficiency and service life.

[0005] To achieve the above object, the present invention provides the following technical solutions:

[0006] A gradient structure of a metal bond sintered grinding wheel, the grinding wheel consisting of a working layer and a non-working layer, the working layer adopts a gradient structure design, including at least three gradient layers distributed along the radial direction, and the metal bond content, abrasive particle size or abrasive type of each gradient layer changes in a gradient.

[0007] Furthermore, in the gradient layers of the working layer, the metal bond content decreases gradually from the outer edge of the grinding wheel to the inner edge, with a gradient of 5-15wt% / layer. This design results in a higher bond content at the outer edge of the grinding wheel, which better holds the abrasive and ensures the initial grinding performance and wear resistance of the grinding wheel. The bond content gradually decreases towards the inner edge, facilitating the timely shedding and renewal of the abrasive, thereby improving grinding efficiency.

[0008] Furthermore, the abrasive particle size of the gradient layer increases gradually from the outer edge of the grinding wheel to the inner edge, ranging from 10 to 200 μm, with a particle size difference of 20 to 50 μm between adjacent gradient layers. This gradient variation in abrasive particle size allows the grinding wheel to use smaller abrasive particles at the outer edge during operation, enabling fine grinding and ensuring surface quality, while using larger abrasive particles towards the inner edge, improving the wheel's cutting ability and grinding efficiency.

[0009] Furthermore, the metal bond is a copper-based, iron-based, or cobalt-based alloy, wherein the copper-based bond contains 50-70 wt% Cu, 10-20 wt% Sn, and 5-15 wt% Ni. These metal bonds have good overall properties and can bond well with the abrasive to meet the performance requirements of the grinding wheel under different working conditions.

[0010] A manufacturing process for the above-mentioned metal bond sintered grinding wheel comprises the following steps:

[0011] S1. Prepare each gradient layer mixture according to the gradient design ratio;

[0012] S2. Using layered loading mold to sequentially fill each gradient layer of mixture;

[0013] S3. Sintering was performed in a stepwise manner under a protective atmosphere, first at 5-10 ° C / min to 600-700 ° C and kept warm for 30-60min, then at 3-5 ° C / min to 800-900 ° C and kept warm for 120-180min;

[0014] S4. After cooling, the product is machined to obtain the finished product.

[0015] Furthermore, in step S2, a centrifugal loading process is used, with a centrifugal force of 200-500G, and the loading order is to fill the material layer by layer from the outer edge layer to the inner edge layer. The centrifugal loading process can make the mixed material more evenly filled, thereby improving the density and performance uniformity of the grinding wheel.

[0016] Furthermore, in step S3, the sintering pressure is 10-30 MPa, and the protective atmosphere is a nitrogen-hydrogen mixed gas (N2:H2=95:5). Appropriate sintering pressure and protective atmosphere help ensure a smooth sintering process and improve the quality of the grinding wheel.

[0017] The manufacturing process further includes a post-processing step S5: laser surface micro-texturing the sintered grinding wheel working layer to form a network of micro-grooves with a depth of 50-200 μm and a spacing of 0.5-2 mm. Laser surface micro-texturing can improve the grinding wheel's chip removal and cooling performance, further enhancing the grinding performance and processing quality of the grinding wheel.

[0018] Furthermore, 0.1-1 wt% of rare earth elements (Y2O3 or La2O3) are added to the gradient layer mixture as a sintering aid. Rare earth elements as sintering aids can improve the sintering performance of the mixture and increase the density and strength of the grinding wheel.

[0019] Compared with the prior art, the present invention has the following beneficial effects:

[0020] 1. The metal bond sintered grinding wheel of the present invention adopts a gradient structure design. By rationally adjusting the metal bond content, abrasive particle size or abrasive type of each gradient layer, the performance of each part of the grinding wheel is optimized, which can not only ensure good initial grinding performance and wear resistance, but also improve grinding efficiency, extend the service life of the grinding wheel, and ensure the quality of the processed surface.

[0021] 2. The manufacturing process utilizes layered loading, centrifugal loading, and stepped temperature sintering to ensure precise shaping of the grinding wheel's gradient structure and excellent performance. The addition of rare earth elements as sintering aids and laser surface micro-texturing of the working layer further enhance the quality and performance of the grinding wheel, enabling it to perform even better in grinding operations.

[0022] The above description is only an overview of the technical solution of the present application. In order to more clearly understand the technical means of the present application so that it can be implemented in accordance with the contents of the specification, and to make the above and other purposes, features and advantages of the present application more obvious and easy to understand, the following is a detailed description of the preferred embodiment of the present application in conjunction with the accompanying drawings.

[0023] Based on the detailed description of the specific embodiments of the present application in conjunction with the accompanying drawings below, those skilled in the art will become more aware of the above and other objects, advantages and features of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the following will briefly introduce the drawings required for the embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present application. For those of ordinary skill in the art, other drawings can also be obtained based on these drawings without inventive work. In all drawings, similar elements or parts are generally identified by similar reference numerals. In the drawings, the elements or parts are not necessarily drawn according to the actual scale.

[0025] Figure 1 It is a structural schematic diagram of the present invention.

[0026] In the figure: 1, working layer; 2, non-working layer. DETAILED DESCRIPTION

[0027] In order to make the purpose, technical solutions and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, rather than all of the embodiments. In the following description, specific details such as specific configurations and components are provided only to help fully understand the embodiments of the present application. Therefore, it should be clear to those skilled in the art that various changes and modifications can be made to the embodiments described herein without departing from the scope and spirit of the present application. In addition, for clarity and brevity, the description of known functions and structures has been omitted in the embodiments.

[0028] In addition, the present application may repeat reference numerals and / or letters in different examples. This repetition is for the purpose of simplicity and clarity and does not in itself indicate the relationship between the various embodiments and / or settings discussed.

[0029] The term "and / or" in this article is only a description of the association relationship of associated objects, indicating that three relationships can exist. For example, A and / or B can mean: A exists alone, B exists alone, and A and B exist at the same time. The term " / and" in this article describes another type of association object relationship, indicating that two relationships can exist. For example, A / and B can mean: A exists alone, and A and B exist alone. In addition, the character " / " in this article generally indicates that the previous and subsequent associated objects are in an "or" relationship.

[0030] It should also be noted that, in this document, relational terms such as first and second are used only to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations. Moreover, the terms "include," "comprises," or any other variations thereof are intended to cover non-exclusive inclusion.

[0031] See also Figure 1 The present invention provides a technical solution for a gradient structure of a metal bonded sintered grinding wheel and a manufacturing process thereof:

[0032] Example 1

[0033] A metal bond sintered grinding wheel was prepared. The working layer adopted a three-layer gradient structure. The metal bond was a copper-based alloy with a composition of 60wt% Cu, 15wt% Sn, and 10wt% Ni. 0.5wt% Y2O3 was added to each gradient layer as a sintering aid.

[0034] The gradient layer mixtures were prepared according to the ratios of 30wt%, 25wt% and 20wt% of metal binder content from the outer edge to the inner edge and 50μm, 80μm and 110μm of abrasive particle size from the outer edge to the inner edge.

[0035] A layered loading mold is used, and under the condition of a centrifugal force of 300G, the gradient layer mixtures are filled in sequence from the outer edge layer to the inner edge layer.

[0036] The sintering was carried out in a step-by-step temperature-raising manner under a protective atmosphere of nitrogen-hydrogen mixed gas (N2:H2=95:5), firstly heating to 650°C at 8°C / min and holding for 45 minutes, then heating to 850°C at 4°C / min and holding for 150 minutes, and the sintering pressure was 20 MPa.

[0037] After cooling, the grinding wheel blank is obtained by machining, and the working layer is subjected to laser surface micro-texturing to form a network of micro-grooves with a depth of 100 μm and a spacing of 1 mm to obtain a finished grinding wheel.

[0038] Example 2

[0039] The working layer also adopts a three-layer gradient structure, the metal binder is an iron-based alloy, and 0.3wt% La2O3 is added to each gradient layer as a sintering aid.

[0040] The metal binder contents from the outer edge to the inner edge are 28 wt%, 23 wt%, and 18 wt%, respectively; and the abrasive particle sizes from the outer edge to the inner edge are 40 μm, 70 μm, and 100 μm, respectively.

[0041] A centrifugal charging process was adopted, the centrifugal force was 250G, and the charging sequence was the same as in Example 1.

[0042] During the sintering process, the temperature was first raised to 680°C at 6°C / min and kept for 50 minutes, then raised to 880°C at 3°C / min and kept for 160 minutes. The sintering pressure was 15 MPa, and the protective atmosphere was a nitrogen-hydrogen mixed gas (N2:H2=95:5).

[0043] After cooling machine processing, the working layer was subjected to laser surface micro-texturing processing to form a network of micro-grooves with a depth of 80 μm and a spacing of 0.8 mm to obtain the finished grinding wheel.

[0044] A grinding performance comparison test was conducted on the grinding wheel prepared in the above embodiment and the traditional uniform structure grinding wheel. Under the same grinding conditions, the grinding efficiency of the grinding wheel of the present invention was improved by 30%-40%, the service life was extended by 2-3 times, and the machined surface roughness was reduced by 20%-30%, verifying the superiority of the technical solution of the present invention.

[0045] The foregoing description is merely a preferred embodiment of the present invention and does not limit the scope of protection of the present invention. Those skilled in the art will readily appreciate that the present invention is susceptible to various modifications and variations. Any variation, modification, replacement, integration, or parameter change to these embodiments, which is within the spirit and principles of the present invention and which achieves the same functionality through conventional substitutions, without departing from the principles and spirit of the present invention, falls within the scope of protection of the present invention.

Claims

1. A gradient structure of a metal bond sintered grinding wheel, characterized by: The grinding wheel is composed of a working layer (1) and a non-working layer (2); the working layer (1) adopts a gradient structure design, including at least three gradient layers (1A, 1B, 1C) distributed along the radial direction; the metal binder content, abrasive particle size or abrasive type of each gradient layer changes in a gradient manner.

2. The gradient structure according to claim 1, characterized in that: In the gradient layer of the working layer (1), the content of the metal binder decreases layer by layer from the outer edge to the inner edge of the grinding wheel, and the decreasing gradient is 5-15wt% / layer.

3. The gradient structure according to claim 1, characterized in that: The abrasive particle size of the gradient layer increases layer by layer from the outer edge to the inner edge of the grinding wheel, the particle size variation range is 10-200 μm, and the particle size difference between adjacent gradient layers is 20-50 μm.

4. The gradient structure according to claim 1, characterized in that: The metal binder is a copper-based, iron-based or cobalt-based alloy, wherein the copper-based binder contains 50-70 wt% Cu, 10-20 wt% Sn and 5-15 wt% Ni.

5. A process for manufacturing the metal bond sintered grinding wheel according to any one of claims 1 to 4, characterized in that The following steps are involved: S1. Prepare each gradient layer mixture according to the gradient design ratio; S2. Using layered loading mold to sequentially fill each gradient layer of mixture; S3. Sintering was performed in a stepwise manner under a protective atmosphere, first at 5-10 ° C / min to 600-700 ° C and kept warm for 30-60min, then at 3-5 ° C / min to 800-900 ° C and kept warm for 120-180min; S4. After cooling, the product is machined to obtain the finished product.

6. The manufacturing process according to claim 5, characterized in that: In step S2, a centrifugal loading process is adopted, the centrifugal force is 200-500G, and the loading order is filling from the outer edge layer to the inner edge layer layer by layer.

7. The manufacturing process according to claim 5, characterized in that: In step S3, the sintering pressure is 10-30 MPa, and the protective atmosphere is a nitrogen-hydrogen mixed gas (N2:H2=95:5).

8. The manufacturing process according to claim 5, characterized in that: The method further includes a post-processing step S5: performing laser surface micro-texturing on the sintered grinding wheel working layer to form a network of micro-grooves with a depth of 50-200 μm and a spacing of 0.5-2 mm.

9. The manufacturing process according to claim 5, characterized in that: 0.1-1 wt% of rare earth elements (Y2O3 or La2O3) are added to the gradient layer mixture as a sintering aid.

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