Preparation method of wear-resistant manganese brass

Abstract

According to the preparation method, the component proportion is redesigned, Mn, S i, Fe and other elements are used for promoting formation of second-phase particles, Cr and the like are used for refining grains, Y, Ce and the like are used for increasing the precipitation number of the second-phase particles, and rolling, stretching treatment, heat treatment and other processes are used for assistance, so that the wear-resistant manganese brass is obtained. And under the cooperation, the wear resistance of the formed multi-element copper alloy is obviously improved.

Description

Technical Field

[0001] The invention relates to the technical field of alloys, and in particular to a method for preparing wear-resistant manganese brass. Background Art

[0002] Cu-Zn alloys are widely used, such as silicon brass and manganese brass. They have excellent performance in terms of cost, casting performance, strength, processing, etc., but poor performance in wear resistance such as hardness. In order to improve its hardness and other properties, the common research and development directions of most companies are such as adding multiple reinforcing elements to the copper alloy components, or adding rare earth elements, etc., and some of them are processed in subsequent rolling, aging and other aspects, but the effect improvement still cannot meet the demand and needs to be improved. Summary of the invention

[0003] To solve at least one of the above technical defects, the present invention provides the following technical solutions:

[0004] This application document discloses a method for preparing wear-resistant manganese brass, comprising the following steps:

[0005] First, the raw materials are melted and cast into ingots. By mass, the raw material components are as follows: Zn 36-38%, Mn 1.6-2.5%, Si 0.3-0.4%, Fe 0.05-0.12%, Mg 0.1-0.3%, Cr 0.05-0.09%, Y 0.03-0.05%, Ce 0.01-0.03%, and Cu balance;

[0006] Second, rolling the ingot, including hot rolling and cold rolling;

[0007] Third, the billet after rolling is stretched;

[0008] Fourth, heat treatment is performed on the blank after stretching treatment.

[0009] In this scheme, the component ratio is redesigned, and elements such as Mn, Si, and Fe are used to promote the formation of second-phase particles, Cr and other elements are used to refine the grains, and Y, Ce and other elements are used to increase the number of precipitation of second-phase particles. In addition, rolling, stretching, heat treatment and other processes are used to coordinate the formed multi-element copper alloy to significantly improve its wear resistance.

[0010] Furthermore, the ingot is heated before rolling at a temperature of 800-850° C. for a time of 1-3 hours.

[0011] Furthermore, the heat treatment in the fourth step is a two-stage heat treatment, wherein the first stage heat treatment temperature is 800±10°C, the time is 1-4h, and the second stage heat treatment temperature is 500-550°C, the time is 1-6h. Under this specific heat treatment process, more slender silicon manganese rings will be formed, thereby further improving the wear resistance of the multi-copper alloy.

[0012] Furthermore, in the third step of stretching treatment, the stretching speed is 4-10 m / min, the stretching coefficient is 1.18-1.2, and the stretching passes are 10 times. The limited parameters help improve the performance of the formed copper alloy.

[0013] Furthermore, the total processing rate of hot rolling is 40-60%, and the total processing rate of cold rolling is 10-20%.

[0014] Furthermore, the total processing rate of hot rolling is 50%, the total processing rate of cold rolling is 20%, the rolling speed is 2-4m / s, the hot rolling passes are 6 times, and the limited rolling speed and rolling processing rate, in combination, help improve the performance of the formed copper alloy.

[0015] Compared with the prior art, the present invention has the following beneficial effects:

[0016] 1. The present invention designs the components and preparation process of manganese brass, and the formed multi-component copper alloy has significantly improved wear resistance. DETAILED DESCRIPTION

[0017] The present invention will be further described below in conjunction with specific embodiments.

[0018] Example 1

[0019] The preparation method of wear-resistant manganese brass comprises the following steps:

[0020] First, the raw materials are melted according to the following ratio at a temperature of 1450±20°C. During the melting process, carbon powder is covered with a thickness of 32 cm. After the raw materials are melted, they are kept warm for 100 minutes. The temperature is lowered to 1250±10°C, and CuP10 (accounting for 0.5% of the weight of the melt) is added for refining. The temperature is kept at 1200°C for 30 minutes. After slag removal, a copper alloy melt is obtained, which is then cast into an ingot.

[0021] By mass, the raw material components are as follows: Zn 36%, Mn 2.0%, Si 0.3%, Fe 0.08%, Mg 0.2%, Cr 0.07%, Y 0.03%, Ce 0.01%, and Cu as the balance.

[0022] Second, the ingot is cut and the cut pieces are rolled, including hot rolling and cold rolling. Before hot rolling, the cut pieces of the ingot are heated to 800°C for 1 hour. The total processing rate of hot rolling is 60%, the rolling speed is 2m / s, and the number of hot rolling passes is 6 times; the total processing rate of cold rolling is 20%, and the rolling speed is 2m / s.

[0023] Third, the billet after rolling is stretched, wherein the stretching speed is 5 m / min, the stretching coefficient is 1.18, and the stretching passes are 10 times.

[0024] Fourth, the blank is heat treated after the stretching treatment, wherein the first heat treatment temperature is 800°C for 3 hours, and the second heat treatment temperature is 500°C for 4 hours.

[0025] Example 2

[0026] The preparation method of wear-resistant manganese brass comprises the following steps:

[0027] First, the raw materials are melted according to the following ratio at a temperature of 1450±20°C. During the melting process, carbon powder is covered with a thickness of 32 cm. After the raw materials are melted, they are kept warm for 100 minutes. The temperature is lowered to 1250±10°C, and CuP10 (accounting for 0.5% of the weight of the melt) is added for refining. The temperature is kept at 1200°C for 30 minutes. After slag removal, a copper alloy melt is obtained, which is then cast into an ingot.

[0028] By mass, the raw material components are as follows: Zn 37%, Mn 2.5%, Si 0.4%, Fe 0.1%, Mg 0.3%, Cr 0.09%, Y 0.04%, Ce 0.02%, and Cu as the balance.

[0029] Second, the ingot is cut and the cut blocks are rolled, including hot rolling and cold rolling. Before hot rolling, the cut ingot blocks are heated to 800°C for 2 hours. The total processing rate of hot rolling is 50%, the rolling speed is 2m / s, and the number of hot rolling passes is 6 times; the total processing rate of cold rolling is 20%, and the rolling speed is 2m / s.

[0030] Third, the billet after rolling is stretched, wherein the stretching speed is 6 m / min, the stretching coefficient is 1.2, and the stretching passes are 10 times.

[0031] Fourth, the blank after stretching treatment is heat treated, wherein the first heat treatment temperature is 805°C, the time is 2h, and the second heat treatment temperature is 500°C, the time is 5h.

[0032] Example 3

[0033] The preparation method of wear-resistant manganese brass comprises the following steps:

[0034] First, the raw materials are melted according to the following ratio at a temperature of 1450±20°C. During the melting process, carbon powder is covered with a thickness of 32 cm. After the raw materials are melted, they are kept warm for 100 minutes. The temperature is lowered to 1250±10°C, and CuP10 (accounting for 0.5% of the weight of the melt) is added for refining. The temperature is kept at 1200°C for 30 minutes. After slag removal, a copper alloy melt is obtained, which is then cast into an ingot.

[0035] By mass, the raw material components are as follows: Zn 38%, Mn 2.2%, Si 0.3%, Fe 0.07%, Mg 0.15%, Cr 0.06%, Y 0.04%, Ce 0.03%, and Cu as the balance.

[0036] Second, the ingot is cut and the cut pieces are rolled, including hot rolling and cold rolling. Before hot rolling, the cut pieces of the ingot are heated to 820°C for 1 hour. The total processing rate of hot rolling is 40%, the rolling speed is 2m / s, and the number of hot rolling passes is 6 times; the total processing rate of cold rolling is 20%, and the rolling speed is 2m / s.

[0037] Third, the billet after rolling is stretched, wherein the stretching speed is 7 m / min, the stretching coefficient is 1.19, and the stretching passes are 10 times.

[0038] Fourth, the blank is heat treated after the stretching treatment, wherein the first heat treatment temperature is 800°C for 1 hour, and the second heat treatment temperature is 500°C for 5 hours.

[0039] Example 4

[0040] The preparation method of wear-resistant manganese brass comprises the following steps:

[0041] First, the raw materials are melted according to the following ratio at a temperature of 1450±20°C. During the melting process, carbon powder is covered with a thickness of 32 cm. After the raw materials are melted, they are kept warm for 100 minutes. The temperature is lowered to 1250±10°C, and CuP10 (accounting for 0.5% of the weight of the melt) is added for refining. The temperature is kept at 1200°C for 30 minutes. After slag removal, a copper alloy melt is obtained, which is then cast into an ingot.

[0042] By mass, the raw material components are as follows: Zn 36%, Mn 1.8%, Si 0.35%, Fe 0.06%, Mg 0.3%, Cr 0.06%, Y 0.04%, Ce 0.03%, and Cu as the balance.

[0043] Second, the ingot is cut and the cut blocks are rolled, including hot rolling and cold rolling. Before hot rolling, the cut ingot blocks are heated to 830°C for 1.5 hours. The total processing rate of hot rolling is 55%, the rolling speed is 2m / s, and the number of hot rolling passes is 6 times; the total processing rate of cold rolling is 20%, and the rolling speed is 2m / s.

[0044] Third, the billet after rolling is stretched, wherein the stretching speed is 6 m / min, the stretching coefficient is 1.18, and the stretching passes are 10 times.

[0045] Fourth, the blank after stretching treatment is heat treated, wherein the first heat treatment temperature is 810°C, the time is 4 hours, and the second heat treatment temperature is 520°C, the time is 4 hours.

[0046] Comparative Example 1

[0047] Compared with Example 1, the heat treatment step in this scheme only includes the second stage of heat treatment.

[0048] Comparative Example 2

[0049] Compared with Example 1, the components of this solution do not contain Mg.

[0050] Comparative Example 3

[0051] Compared with Example 1, the components of this solution do not contain Mg, and the heat treatment step only includes the second heat treatment.

[0052] The properties of the formed copper alloy were tested, as shown in Table 1.

[0053] Table 1

[0054] Brinell hardness HBW Example 1 208.6 Example 2 194.3 Example 3 185.8 Example 4 210.9 Comparative Example 1 137.6 Comparative Example 2 147 Comparative Example 3 100.2

[0055] It can be seen that the copper alloy prepared in this scheme has significantly improved hardness. In the subsequent wear detection (dry sliding wear test through pin-disc configuration), the wear amount of Examples 1-4 is less than 6.0 mg, and the wear amount of Comparative Examples 1-3 is above 6.7.

[0056] According to our company's detection and existing theoretical speculation, the principle is as follows: Mn, Si, Fe, etc. promote the formation of second phase particles, and help limit the morphology of second phase particles through Mn, Si, Fe, etc., and cooperate with Cr, Mg, etc. to refine the grains and homogenize their distribution. High temperature treatment in heat treatment helps to increase the solid solution amount of silicon and manganese phases, and Mg and other elements are dissolved under cooling to form an elongated shape. Y elements and other elements increase the number of second phase particles. The surface distribution of a large number of elongated second phase particles greatly improves hardness.

[0057] The above are only preferred embodiments of the present invention. The protection scope of the present invention is not limited to the above embodiments. All technical solutions under the concept of the present invention belong to the protection scope of the present invention. It should be pointed out that for ordinary technicians in this technical field, some improvements and modifications without departing from the principle of the present invention should also be regarded as the protection scope of the present invention.

Claims

1. A method for preparing wear-resistant manganese brass, characterized in that: The following steps are involved: First, the raw materials are melted and cast into ingots. By mass, the raw material components are as follows: Zn 36-38%, Mn 1.6-2.5%, Si 0.3-0.4%, Fe 0.05-0.12%, Mg 0.1-0.3%, Cr 0.05-0.09%, Y 0.03-0.05%, Ce 0.01-0.03%, and Cu balance; Second, rolling the ingot, including hot rolling and cold rolling; Third, the billet after rolling is stretched; Fourth, heat treatment is performed on the blank after stretching treatment.

2. The method for preparing wear-resistant manganese brass according to claim 1, characterized in that: The ingot is heated before rolling at a temperature of 800-850°C for 1-3 hours.

3. The method for preparing wear-resistant manganese brass according to claim 1, characterized in that: In the fourth step, the heat treatment is a two-stage process, wherein the first stage is at a temperature of 800±10°C for 1-4 hours, and the second stage is at a temperature of 500-550°C for 1-6 hours.

4. The method for preparing wear-resistant manganese brass according to claim 1, characterized in that: In the third step of stretching, the stretching speed is 4-10 m / min, the stretching coefficient is 1.18-1.2, and the stretching passes are 10 times.

5. The method for preparing wear-resistant manganese brass according to claim 1, characterized in that: The total processing rate of hot rolling is 40-60%, and the total processing rate of cold rolling is 10-20%.

6. The method for preparing wear-resistant manganese brass according to claim 5, characterized in that: The total processing rate of hot rolling is 50%, the total processing rate of cold rolling is 20%, the rolling speed is 2-4m / s, and the hot rolling passes are 6 times.