Wear-resistant powder metallurgy material and preparation method thereof

Abstract

The invention relates to the technical field of powder metallurgy preparation, in particular to a wear-resistant powder metallurgy material and a preparation method thereof.The wear-resistant powder metallurgy material comprises, by mass, 34.5% of wear-resistant powder T400, 44% of alloy high-speed steel basic powder, 20% of basic iron powder, 0.5% of a lubricant and 1% of an additive. Repeated pressing and sintering are not needed, the process steps are simple, the efficiency is high, the yield is high, and batch production is easy; in addition, the green body and the copper permeating sheet are not prone to breakage after being sintered, the problem that the bimetallic material is prone to cracking and layering is solved, more equipment and facility investment do not need to be additionally added, energy consumption cannot be increased, and environmental protection cannot be affected.

Description

Technical Field

[0001] The invention relates to the technical field of powder metallurgy preparation, in particular to a wear-resistant powder metallurgy material and a preparation method thereof. Background Art

[0002] Powder metallurgy is a process for producing metal powders and using forming and sintering processes to make metal powders into materials or products. Currently, there are two typical technologies on the market:

[0003] The first is bimetallic materials: this technology is to use two different metal materials to fill the mold in sequence during pressing. First, fill the base powder into the non-working area of ​​the product, then fill the wear-resistant powder into the working area of ​​the product, and then press and sinter to form. This technology reduces the overall load during pressing, while ensuring that the working area of ​​the product is completely covered by the wear-resistant material to meet the performance and functional requirements of the product. However, the disadvantage of this method is that the material stability is poor, and cracks are prone to occur at the connection between the two metal materials during actual use;

[0004] The second type is re-pressing and re-firing materials: This technology is to perform multiple pressing and sintering on the traditional powder metallurgy pressing technology to obtain high-quality products. This technology requires special equipment and facilities to implement, including more presses and sintering furnaces. These equipment not only need to occupy a larger site area, but also need more maintenance and management. At the same time, because the re-pressing and sintering require higher pressure and temperature, the energy consumption of the re-pressing and re-firing technology is greatly increased, and the efficiency is low, which not only increases the production cost but also has a certain impact on the environment, so it needs to be improved. Summary of the invention

[0005] The object of the present invention is to provide a wear-resistant powder metallurgy material and a preparation method thereof to solve the problems raised in the above background technology.

[0006] To achieve the above object, the present invention provides the following technical solutions:

[0007] A wear-resistant powder metallurgy material comprises the following components by mass: 30%-40% of wear-resistant powder T400, 40%-50% of alloy high-speed steel basic powder, 15%-25% of basic iron powder, 0.2%-0.8% of lubricant, and 0.5%-1.5% of additives.

[0008] Specifically, the composition comprises, by mass: 34.5% of wear-resistant powder T400, 44% of alloy high-speed steel basic powder, 20% of basic iron powder, 0.5% of lubricant, and 1% of additive.

[0009] The present invention also provides a method for preparing a wear-resistant powder metallurgy material, which specifically comprises the following steps:

[0010] S1. Incoming inspection process: First of all, the quality of raw materials must be monitored to ensure that the incoming materials meet the requirements of industry standards; usually the first-in-first-out and batch management methods are adopted;

[0011] S2, mixing process: then according to the material formula, weigh the set mass of wear-resistant powder T400, alloy high-speed steel base powder, base iron powder, lubricant, additives and appropriate amount of water in a certain proportion and mechanically stir and mix them to obtain a mixed solution; the mixing time is 15min-30min;

[0012] S3. Fluidity test of mixed solution: Use Hall flowmeter to test the flow rate of mixed solution. If the flow rate of mixed solution is less than or equal to 50s / 50g, proceed with subsequent work normally. If the flow rate of mixed solution is greater than 50s / 50g, the mixing time needs to be reduced and the proportion of ingredients needs to be adjusted if necessary until the flow rate of mixed solution is less than or equal to 50s / 50g. Only then can subsequent work be carried out normally.

[0013] S4, green body pressing process: a mixed solution is mixed in a desired ratio, and a mold of a desired geometric shape is used to mechanically press the mixed solution to obtain a green body;

[0014] S5, copper-infiltrated sheet pressing process: after the green body is pressed, the copper-infiltrated sheet is pressed according to the weight of the single green body and the weight ratio of the green body is 10%-18%; a mold with the same geometric shape as that of the green body is selected to press the copper-infiltrated powder to obtain the copper-infiltrated sheet;

[0015] S6, sintering process: the pressed green body and the copper-infiltrated sheet are overlapped one by one, wherein the copper-infiltrated sheet is at the bottom and the green body is at the top, and the assembled pressed product is placed in a sintering device, heated to a certain temperature and sintered to obtain powder metallurgy;

[0016] S7, cold and hot treatment process: After the powder metallurgy is sintered, it is immersed in liquid nitrogen at -196℃ for 30 minutes for deep cold treatment, and then heated to 538℃ and kept warm for 1 hour for heat treatment;

[0017] S8, Physical and chemical performance testing process: Use various inspection tools to test the product to ensure that it meets the expected design requirements;

[0018] S9. After passing the inspection, the products are packaged and put into storage.

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

[0020] The preparation method of the wear-resistant powder metallurgy material only needs to be pressed twice and sintered once, and repeated pressing and sintering are not required, so the process steps are simple, the efficiency is high, the yield is high, and batch production is easy; in addition, the green body and the copper-infiltrated sheet are not prone to fracture after sintering, which solves the problem that the bimetallic material is prone to cracking and delamination, and there is no need to increase the investment in additional equipment and facilities, and the energy consumption will not increase, and environmental protection will not be affected in any way. DETAILED DESCRIPTION

[0021] The technical solutions in the embodiments of the present invention are described clearly and completely below. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0022] The present invention provides a technical solution:

[0023] A wear-resistant powder metallurgy material comprises the following components by mass: 30%-40% of wear-resistant powder T400, 40%-50% of alloy high-speed steel basic powder, 15%-25% of basic iron powder, 0.2%-0.8% of lubricant, and 0.5%-1.5% of additives.

[0024] Specifically, the composition comprises, by mass: 34.5% of wear-resistant powder T400, 44% of alloy high-speed steel basic powder, 20% of basic iron powder, 0.5% of lubricant, and 1% of additive.

[0025] The present invention also provides a method for preparing a wear-resistant powder metallurgy material, which specifically comprises the following steps:

[0026] S1. Incoming inspection process: First of all, the quality of raw materials must be monitored to ensure that the incoming materials meet the requirements of industry standards; usually the first-in-first-out and batch management methods are adopted;

[0027] S2, mixing process: then according to the material formula, weigh the set mass of wear-resistant powder T400, alloy high-speed steel base powder, base iron powder, lubricant, additives and appropriate amount of water in a certain proportion and mechanically stir and mix them to obtain a mixed solution; the mixing time is 15min-30min;

[0028] S3. Fluidity test of mixed solution: Use Hall flowmeter to test the flow rate of mixed solution. If the flow rate of mixed solution is less than or equal to 50s / 50g, proceed with subsequent work normally. If the flow rate of mixed solution is greater than 50s / 50g, the mixing time needs to be reduced and the proportion of ingredients needs to be adjusted if necessary until the flow rate of mixed solution is less than or equal to 50s / 50g. Only then can subsequent work be carried out normally.

[0029] S4, green body pressing process: a mixed solution is mixed in a desired ratio, and a mold of a desired geometric shape is used to mechanically press the mixed solution to obtain a green body;

[0030] S5, copper-infiltrated sheet pressing process: after the green body is pressed, the copper-infiltrated sheet is pressed according to the weight of the single green body and the weight ratio of the green body is 10%-18%; a mold with the same geometric shape as that of the green body is selected to press the copper-infiltrated powder to obtain the copper-infiltrated sheet;

[0031] S6, sintering process: the pressed green body and the copper-infiltrated sheet are overlapped one by one, wherein the copper-infiltrated sheet is at the bottom and the green body is at the top, and the assembled pressed product is placed in a sintering device, and heated to a certain temperature for sintering to obtain powder metallurgy; the sintering device includes a preheating zone and a sintering zone, after the pressed green body and the copper-infiltrated sheet are overlapped one by one, they are first preheated in the preheating zone and then sintered in the sintering zone, and the temperature during the preheating process should be slowly increased in a step-by-step manner, and the temperature change is set to 760°C, 850°C, and 950°C;

[0032] S7, cold and hot treatment process: After the powder metallurgy is sintered, it is immersed in liquid nitrogen at -196℃ for 30 minutes for deep cold treatment, and then heated to 538℃ and kept warm for 1 hour for heat treatment;

[0033] S8, Physical and chemical performance testing process: Use various inspection tools to test the product to ensure that it meets the expected design requirements;

[0034] S9. After passing the inspection, the products are packaged and put into storage.

Claims

1. A wear-resistant powder metallurgy material, characterized in that: The composition comprises the following components by mass: 30%-40% of wear-resistant powder T400, 40%-50% of alloy high-speed steel basic powder, 15%-25% of basic iron powder, 0.2%-0.8% of lubricant, and 0.5%-1.5% of additives.

2. The wear-resistant powder metallurgy material according to claim 1, characterized in that: The composition includes, by mass: 34.5% of wear-resistant powder T400, 44% of alloy high-speed steel basic powder, 20% of basic iron powder, 0.5% of lubricant, and 1% of additive.

3. A method for preparing a wear-resistant powder metallurgy material, using the wear-resistant powder metallurgy material according to claim 1, characterized in that: The specific steps include: S1. Incoming inspection process: First of all, the quality of raw materials must be monitored to ensure that the incoming materials meet the requirements of industry standards; usually the first-in-first-out and batch management methods are adopted; S2, mixing process: then according to the material formula, weigh the set mass of wear-resistant powder T400, alloy high-speed steel base powder, base iron powder, lubricant, additives and appropriate amount of water in a certain proportion and mechanically stir and mix them to obtain a mixed solution; the mixing time is 15min-30min; S3. Fluidity test of mixed solution: Use Hall flowmeter to test the flow rate of mixed solution. If the flow rate of mixed solution is less than or equal to 50s / 50g, proceed with subsequent work normally. If the flow rate of mixed solution is greater than 50s / 50g, the mixing time needs to be reduced and the proportion of ingredients needs to be adjusted if necessary until the flow rate of mixed solution is less than or equal to 50s / 50g. Only then can subsequent work be carried out normally. S4, green body pressing process: a mixed solution is mixed in a desired ratio, and a mold of a desired geometric shape is used to mechanically press the mixed solution to obtain a green body; S5, copper-infiltrated sheet pressing process: after the green body is pressed, the copper-infiltrated sheet is pressed according to the weight of the single green body and the weight ratio of the green body is 10%-18%; a mold with the same geometric shape as that of the green body is selected to press the copper-infiltrated powder to obtain the copper-infiltrated sheet; S6, sintering process: the pressed green body and the copper-infiltrated sheet are overlapped one by one, wherein the copper-infiltrated sheet is at the bottom and the green body is at the top, and the assembled pressed product is placed in a sintering device, heated to a certain temperature and sintered to obtain powder metallurgy; S7, cold and hot treatment process: After the powder metallurgy is sintered, it is immersed in liquid nitrogen at -196℃ for 30 minutes for deep cold treatment, and then heated to 538℃ and kept warm for 1 hour for heat treatment; S8, Physical and chemical performance testing process: Use various inspection tools to test the product to ensure that it meets the expected design requirements; S9. After passing the inspection, the products are packaged and put into storage.

4. The method for preparing a wear-resistant powder metallurgy material according to claim 3, characterized in that: The sintering equipment in step S6 includes a preheating zone and a sintering zone. After the green body and the copper-infiltrated sheet are pressed and overlapped one by one, they are first preheated in the preheating zone and then sintered in the sintering zone. The temperature during the preheating process should rise slowly in steps, and the temperature change is set to 760°C, 850°C, and 950°C.