CN108118168B

CN108118168B - Forming method of ultrahigh-temperature wear-resistant alloy

Info

Publication number: CN108118168B
Application number: CN201711392801.7A
Authority: CN
Inventors: 刘清杰
Original assignee: Sichuan Aerospace Vocational College
Current assignee: Sichuan Aerospace Vocational College
Priority date: 2017-12-21
Filing date: 2017-12-21
Publication date: 2020-10-09
Anticipated expiration: 2037-12-21
Also published as: CN108118168A

Abstract

The invention provides a molding method of an ultrahigh-temperature wear-resistant alloy, which comprises the following steps: (1) preparing raw materials, wherein the raw materials comprise the following components in percentage by weight: 15-25% of Al, 15-20% of Zn, 12-15% of Co, 10-12% of Ni, 3-5% of Mn, 3-5% of Si, 1% of Bi and 1% of La, and the balance of Cu and inevitable impurities; (2) melting the Al-Cu alloy at 1150-1250 ℃; and then, adding the rest raw materials, smelting at 1550-1650 ℃, preserving heat for 2-3 hours, and then carrying out casting molding. The alloy has excellent high-temperature resistance, and can have tensile strength of 150-155 MPa and elongation of 87% at 1150 ℃; meanwhile, the alloy obtained by the invention has excellent wear resistance and corrosion resistance. The alloy has wide application range and can be applied to special equipment.

Description

Forming method of ultrahigh-temperature wear-resistant alloy

Technical Field

The invention belongs to the technical field of alloys, and particularly relates to a forming method of an ultrahigh-temperature wear-resistant alloy.

Background

With the continuous development of engineering technology, the requirements of mechanical materials such as blast furnaces, engines and the like on high temperature resistance and wear resistance are higher and higher, and on the basis, the materials are also required to have excellent corrosion resistance.

The traditional high-temperature resistant alloy is mainly Ni-Cr series, Ni-Fe-Cr series and Ni-Cr-Mo series alloy, and the alloys can bear certain stress at the temperature of 600 ℃. However, due to the development of engineering techniques, there is an urgent need for alloy materials that can withstand higher temperatures. In the research direction, the high-temperature alloy Haynes230 developed in the United states has the high-temperature strength of 135Pa at 1100 ℃, the elongation of 85 percent and the components of Ni-22Cr-14W-0.5Mn-0.4Si-0.02 La. The alloy improves the strength of a matrix by adding W and Cr.

In the aspect of development of corrosion-resistant alloys, the first industrial corrosion-resistant alloy is Monel 400 which is a Ni-Cu alloy and has excellent performance of resisting corrosion of reducing acid, strong alkaline medium, seawater and the like. Later, HastelloyA, a Ni-Mo alloy, was developed, but has the disadvantage of being used only for hydrochloric acid corrosion resistance at 70 ℃ and has been rarely used at present. On the basis of the above-mentioned studies, various Ni-Cr-Fe, Ni-Cr-Si and Ni-Cr-Mo alloys have been developed. However, these alloys are typically used at very low temperatures, only below 600 ℃ (e.g., Incoloy800 alloy).

Although the service temperature of the corrosion-resistant alloy prepared by people has been raised to 950-1000 ℃ in more than ten years, the improvement space is still provided to meet higher engineering requirements.

Disclosure of Invention

In view of the defects of the prior art, the invention aims to provide a forming method of an ultrahigh-temperature wear-resistant alloy, which comprises the following steps:

(1) preparing raw materials, wherein the raw materials comprise the following components in percentage by weight:

30-35% of Al, 15-20% of Zn, 12-15% of Co, 10-12% of Ni, 3-5% of Mn, 3-5% of Si, 1% of Bi and 1% of La, and the balance of Cu and inevitable impurities; wherein Al and Si are present in the form of an Al-Cu alloy;

(2) melting the Al-Cu alloy at 1150-1250 ℃, and preserving heat or not; and then, adding the rest raw materials, smelting at 1550-1650 ℃, preserving heat for 2-3 hours, and then carrying out casting molding.

According to the invention, through the adjustment of alloy raw materials, the alloy material which can reach the tensile strength of 170-175 MPa at 950 ℃, 150-155 MPa at 1150 ℃ and the elongation of 87% is obtained.

Experiments prove that the alloy disclosed by the invention has no cracking and macroscopic corrosion phenomena after being used for 5 hours, 24 hours and 3 days at 1050 ℃.

The inventors of the present invention have found no cobalt ion or nickel ion after acid etching the alloy obtained by the present invention with the acid etching solution prepared by the method of ISO10271, and also can show that the alloy of the present invention has excellent corrosion resistance from this point of view.

When the alloy is tested on an M-2000 type friction and wear testing machine for the wear resistance of the alloy, when the load is 200N, the friction coefficient is 0.1736, and the wear rate is 0.0063mg/M, which shows that the alloy has good wear resistance.

In a preferred embodiment of the present invention, the weight ratio of Ni to Mn in the composition ratio of the raw material is 3: 1.

In a preferred embodiment of the present invention, the weight ratio of Zn to Co in the raw material is 1.1: 1.

In a preferable embodiment of the present invention, in the step (2), the Al-Cu alloy is melted at 1150 to 1250 ℃ and heat is preserved for 1 to 2 hours.

As an alternative of the invention, the Zn, Ni and Mn are added in the form of a Zn-Ni-Mn prealloy.

The total amount of the inevitable impurities is not more than 0.02%. Specifically, the content of Fe in the inevitable impurities is not more than 0.005%.

The invention has the beneficial effects that:

the alloy has excellent high-temperature resistance, and can have tensile strength of 150-155 MPa and elongation of 87% at 1150 ℃; meanwhile, the alloy obtained by the invention has excellent wear resistance and corrosion resistance. The alloy has wide application range and can be applied to special equipment.

Detailed Description

The present invention is described in detail below by way of examples, and it should be noted that the following examples are only for illustrating the present invention and should not be construed as limiting the scope of the present invention.

Example 1

15% of Al, 15% of Zn, 15% of Co, 12% of Ni, 5% of Mn, 3% of Si, 1% of Bi, 1% of La, and the balance of Cu and inevitable impurities; controlling the total amount of inevitable impurities not to be higher than 0.02%, wherein the content of Fe is not more than 0.005%;

wherein Al and Cu are present in the form of an Al-Cu alloy;

(2) melting the Al-Cu alloy at 1250 ℃, and preserving heat for 2 hours; then, the rest raw materials are added, melted at 1550 ℃, kept warm for 3 hours and then cast and molded.

The obtained alloy is subjected to a high-temperature strength test, and the obtained alloy has the tensile strength of 170MPa at 950 ℃, the tensile strength of 150MPa at 1150 ℃ and the elongation of 87.3 percent.

Example 2

18.7% of Al, 20% of Zn, 13.2% of Co, 10% of Ni, 4% of Mn, 4.4% of Si, 1% of Bi, 1% of La, and the balance of Cu and inevitable impurities; controlling the total amount of inevitable impurities not to be higher than 0.02%, wherein the content of Fe is not more than 0.005%;

wherein Al and Cu are present in the form of an Al-Cu alloy;

The obtained alloy is subjected to a high-temperature strength test, and the obtained alloy has the tensile strength of 172MPa at 950 ℃, the tensile strength of 155MPa at 1150 ℃ and the elongation of 87 percent.

Example 3

18.7% of Al, 15.4% of Zn, 14% of Co, 12% of Ni, 3% of Mn, 3% of Si, 1% of Bi, 1% of La, and the balance of Cu and inevitable impurities; controlling the total amount of inevitable impurities not to be higher than 0.02%, wherein the content of Fe is not more than 0.005%;

wherein Al and Cu are present in the form of an Al-Cu alloy;

The obtained alloy is subjected to a high-temperature strength test, and the obtained alloy has the tensile strength of 175MPa at 950 ℃, the tensile strength of 155MPa at 1150 ℃ and the elongation of 87 percent.

Example 4

25% of Al, 15.4% of Zn, 14% of Co, 10.7% of Ni, 4.8% of Mn, 4.4% of Si, 1% of Bi, 1% of La, and the balance of Cu and inevitable impurities; controlling the total amount of inevitable impurities not to be higher than 0.02%, wherein the content of Fe is not more than 0.005%;

wherein Al and Cu are present in the form of an Al-Cu alloy;

The obtained alloy is subjected to a high-temperature strength test, and the obtained alloy has the tensile strength of 174MPa at 950 ℃, the tensile strength of 154MPa at 1150 ℃ and the elongation of 87 percent.

Comparative example 1

The procedure was as in example 3 except that no Bi was added.

Comparative example 2

The procedure of example 3 was repeated, except that the amount of Ni added was 15%, the amount of Bi added was 0.8%, and the amount of Si added was 5.5%.

Experimental example 1

The alloys obtained in example 3, comparative example 1 and comparative example 2 were tested for wear and corrosion resistance. An abrasion resistance experiment is carried out by adopting an M-2000 type friction abrasion tester, and the friction coefficient of the alloy obtained in the example 3 is 0.1736 and the abrasion rate is 0.0063mg/M when the load is 200N; while the wear rates of comparative examples 1 and 2 were as high as 0.122mg/m and 0.064 mg/m.

Preparing a corrosive liquid: 10.0g of 90% C was added to 300mL of distilled water₃H₆O₃(analytically pure) and 5.85g NaCl, and the solution was then diluted to 1000mL, pH 2.3.

The alloys obtained in example 3, comparative example 1 and comparative example 2 were placed in an etching solution, the etching solution was taken out after being left at 37 ℃ for 7 days, and the concentrations of Co and Ni ions in the etching solution were measured by an inductively coupled plasma emission spectrometer, and it was found that cobalt ions and nickel ions were not detected in the etching solution after the alloy obtained in example 3 was immersed in the etching solution, whereas cobalt ions in the etching solution were 1.5 × 10 respectively after the alloys obtained in comparative example 1 and comparative example 2 were immersed in the etching solution^-4g/L and 2.7 × 10^-4g/L, the nickel ions in the corrosion solution after the alloys obtained in the comparative examples 1 and 2 are soaked in the corrosion solution are respectively 7.9 × 10^-5g/L and 3.1 × 10^- ⁵g/L。

Claims

1. The forming method of the ultrahigh-temperature wear-resistant alloy is characterized by comprising the following steps:

15-25% of Al, 15-20% of Zn, 12-15% of Co, 10-12% of Ni, 3-5% of Mn, 3-5% of Si, 1% of Bi and 1% of La, and the balance of Cu and inevitable impurities; wherein Al and Cu are present in the form of an Al-Cu alloy;

2. The method of claim 1, wherein the raw materials are in a compositional ratio of Ni to Mn of 3:1 by weight.

3. The method of claim 2, wherein the raw materials have a composition ratio of 1.1:1 by weight of Zn to Co.

4. The method as claimed in claim 2, wherein the Al-Cu alloy is melted at 1150-1250 ℃ in the step (2), and the heat is preserved for 1-2 hours.

5. The method of claim 2, wherein the Zn, Ni and Mn are added as a Zn-Ni-Mn prealloy.

6. The method according to claim 1, characterized in that the total amount of unavoidable impurities is not higher than 0.02%.

7. The method according to claim 6, wherein the content of Fe in the inevitable impurities is not more than 0.005%.