Cr-Mo-Nb alloy and production method thereof

Abstract

The invention discloses a Cr-Mo-Nb alloy and a production method thereof, belongs to the field of metal regeneration and cyclic utilization, and solves the problem that the treatment mode of an existing high-temperature alloy difficult-to-treat material is backward. The alloy comprises the following chemical components in percentage by mass: 22-26% of Mo, 9-13% of Nb, less than or equal to 2% of C and the balance of Cr and inevitable impurity elements, and the production method comprises the following production steps: briquetting one or more of nickel-based alloys to generate an alloy briquetting; then smelting is conducted, the smelted alloy is subjected to water quenching through a nickel sulfate solution, and alloy particles are generated; then carbonylation synthesis treatment is carried out, nickel carbonyl and carbonylation slag are obtained after carbonylation synthesis treatment, the carbonylation slag is subjected to hydraulic classification, and the carbonylation slag is divided into a light component material and a heavy component material; and mixing the heavy component material with graphite powder, briquetting, and carrying out reduction roasting to obtain the Cr-Mo-Nb alloy. The device saves time and labor, is high in adaptability, can effectively treat difficult-to-treat materials piled up for a long time in a factory, and greatly facilitates work of the factory.

Description

Technical Field

[0001] The invention belongs to the field of metal recycling and reuse, and specifically relates to a Cr-Mo-Nb alloy and a production method thereof. Background Art

[0002] For the processing of high-temperature alloy return materials, the industry must first classify them by brand, and then process them according to the fixed process according to the different types of return materials. Finally, the processed return materials are added in proportion to produce the same brand of high-temperature alloy master alloy.

[0003] The same grade of high-temperature alloy return materials can be divided into three categories according to the processing flow: direct processing materials, indirect processing materials and difficult-to-process materials. Direct processing materials refer to high-temperature alloy return materials that can be directly added in proportion after raw material pretreatment and vacuum induction melting process; indirect processing materials refer to materials with large shapes and non-metallic impurities that are difficult to separate adhered to the surface of the materials. They can be used as direct processing materials after purification smelting processes such as non-vacuum medium frequency melting, slag purification, etc.; difficult-to-process materials refer to return materials that cannot be effectively processed by the above two methods, including slag-containing materials left over from master alloy injection, turning, slag, grinding steel powder and other materials, and slag-containing materials left over from precision manufacturing injection, etc.

[0004] The industry currently basically handles difficult-to-process materials for casting high-temperature alloys in the form of stockpiling. Some individual companies also sell them at a price based on precious metals such as nickel and cobalt, and sell base metals such as chromium or metals with low content at no price, for use in the smelting of low-quality alloy steel. Summary of the invention

[0005] The invention provides a Cr-Mo-Nb alloy and a production method thereof, so as to solve the problem that the existing treatment method of high-temperature alloy difficult-to-treat materials is backward.

[0006] The technical solution of the present invention is: a Cr-Mo-Nb alloy, the chemical composition and mass percentage of the alloy are: Mo: 22%-26%, Nb: 9%-13%, C≤2%, and the balance is Cr and inevitable impurity elements.

[0007] A method for producing a Cr-Mo-Nb alloy comprises the following steps: A. One or more of the nickel-based alloy K418A, K418B, and K418C slags are subjected to briquetting to form alloy briquette; B. placing the alloy briquette into an electric arc furnace for melting, and quenching the melted alloy with a nickel sulfate solution to generate alloy particles; C. Carbohydrating the alloy particles to obtain carbonyl nickel and carbonyl slag after carbonyl synthesis, and hydraulically classifying the carbonyl slag to separate the carbonyl slag into light component materials and heavy component materials; D. The heavy component material after hydraulic classification and graphite powder are mixed and pressed into a mass, and then placed in a muffle furnace for reduction roasting to obtain a Cr-Mo-Nb alloy.

[0008] As a further improvement of the present invention, in step A, the nickel-based alloys K418A, K418B, and K418C are raw materials for alloys of the original grades that cannot be produced and regenerated by vacuum induction melting, medium frequency melting, and the like, and also cannot be regenerated into raw materials for alloys of the original grades by vacuum induction melting, medium frequency melting, and the like.

[0009] As a further improvement of the present invention, in step B, the concentration of the nickel sulfate solution is 1 to 100 g / L, and the flow rate of the water quenching liquid is 0.1 to 5 m / s.

[0010] As a further improvement of the present invention, in step C, the synthesis pressure is 1-9 MPa and the temperature is ≤250° C., and the produced carbonyl nickel is decomposed to generate carbonyl nickel powder for preparing nickel sulfate.

[0011] As a further improvement of the present invention, in step C, the hydraulic classification water flow velocity is 1-10 m / s, and the hydraulic classification light component material obtained can be directly used in the production of building materials.

[0012] As a further improvement of the present invention, in step C, the carbonyl nickel obtained after carbonylation treatment is decomposed to generate carbonyl nickel powder, and the carbonyl nickel powder can be directly used to prepare the nickel sulfate solution used in step B, and the decomposition temperature is 180-300°C.

[0013] As a further improvement of the present invention, in step D, the particle size of the graphite powder is ≤0.1 mm, the mass percentage of the graphite powder is ≤5%, and the reduction roasting temperature is 850-1280°C.

[0014] The beneficial effects of the present invention are: 1. The present invention regenerates the slag-containing materials K418A, K418B, and K418C, which are difficult-to-treat materials stored for a long time in the casting high-temperature alloy industry, into high-temperature alloys, and smelts them into Cr-Mo-Nb alloys through vacuum smelting to produce Cr, Mo, and Nb raw materials, which effectively helps to treat the difficult-to-treat materials in the factory; 2. The Cr-Mo-Nb alloy produced by the present invention has high purity and low oxygen and nitrogen content, which is convenient for segregation and slag control in the vacuum induction melting process of casting high-temperature alloys K418A, K418B, and K418C, thereby improving the alloy product quality of nickel-based alloys K418A, K418B, and K418C. At the same time, nickel in the slag of K418A, K418B, and K418C alloys is effectively recovered, and the generated carbonyl nickel can be directly used for the preparation of nickel sulfate after decomposition.

[0015] 3. The carbonylation treatment used in the present invention is a method of metallurgy using metal carbonyl compounds, which can selectively convert the metal nickel in the target raw material into a carbonyl compound, while leaving other impurity metals in the residue, thereby achieving efficient separation and purification. However, carbonylation metallurgy has certain requirements for raw materials, among which the S content in the raw materials is a key factor. In the water quenching process, the addition of nickel sulfate solution not only supplements the S element to the raw materials of the carbonylation process, but also does not add an additional S supplementation process, thereby simplifying the process flow.

[0016] 4. The present invention saves time and effort, has strong adaptability, can effectively handle difficult-to-handle materials that have been stored in factories for a long time, and greatly facilitates factory work. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 The figure is a flow chart for preparing the Cr-Mo-Nb alloy of the present invention. DETAILED DESCRIPTION

[0018] The present invention is further described in detail below in conjunction with the accompanying drawings and specific embodiments.

[0019] Embodiment 1, like Figure 1 As shown, the nickel-based alloy K418B slag is first briquette-pressed, and the obtained metal block is placed in an electric arc furnace for smelting. After the smelting is completed, water quenching is performed to obtain alloy particles. The nickel sulfate concentration of the water quenching liquid is 1g / L, and the flow rate of the water quenching liquid is 0.1m / s. The obtained alloy particles are then carbonyl-synthesized, and the obtained carbonyl nickel enters the subsequent decomposition process to prepare carbonyl nickel powder for nickel sulfate. The obtained carbonyl slag is hydraulically classified. The pressure of the carbonyl synthesis is controlled at 1.0MPa, the temperature is controlled at 150±5℃, the decomposition temperature of the carbonyl nickel is controlled at 180~300℃; the water flow rate of the hydraulic classification is 1m / s.

[0020] Finally, the obtained hydraulically classified heavy components are mixed with graphite powder, pressed into a mass, and placed in a muffle furnace for reduction roasting to obtain a Cr-Mo-Nb alloy; the particle size of the graphite powder does not exceed 0.1 mm, the mass percentage of the graphite powder is 0.5%, and the reduction roasting temperature is controlled at 850±5°C.

[0021] After testing, the Cr-Mo-Nb alloy prepared in this embodiment has an oxygen content of 11 ppm, a nitrogen content of 10.5 ppm, a C content of 1.2%, a Mo content of 24.1%, a Nb content of 11.2%, and the remainder is Cr and unavoidable impurities. The alloy can be used for vacuum induction melting of nickel-based alloy K418B.

[0022] Embodiment 2, First, the nickel-based alloy K418B slag is briquetted, and the obtained metal block is placed in an electric arc furnace for smelting. After the smelting is completed, it is water quenched to obtain alloy particles. The nickel sulfate concentration of the water quenching liquid is 100g / L, and the flow rate of the water quenching liquid is 5m / s. The alloy particles obtained in step 2 are then carbonylated and synthesized, and the obtained carbonyl nickel enters the subsequent decomposition process to prepare carbonyl nickel powder for nickel sulfate; the obtained carbonyl slag is hydraulically graded. The pressure of the carbonyl synthesis is controlled at 9.0MPa, the temperature is controlled at 250±5℃, and the decomposition temperature of the carbonyl nickel is controlled at 180-300℃; the water flow rate of the hydraulic classification is 10m / s.

[0023] Finally, the obtained hydraulically classified heavy components are mixed with graphite powder, pressed into a mass, and placed in a muffle furnace for reduction roasting to obtain a Cr-Mo-Nb alloy; the particle size of the graphite powder does not exceed 0.1 mm, the mass percentage of the graphite powder is 5%, and the reduction roasting temperature is controlled at 1280±5°C.

[0024] After testing, the mass content of oxygen in the Cr-Mo-Nb alloy prepared in this embodiment is 18.0ppm, the mass content of nitrogen is 11.6ppm, the mass content of C is 0.1%, the mass content of Mo is 24.6%, the mass content of Nb is 11.5%, and the balance is Cr and unavoidable impurities. The alloy can be used for vacuum induction melting of nickel-based alloy K418B.

[0025] Embodiment 3, First, the nickel-based alloy K418A and nickel-based alloy K418B slag materials are mixed and pressed into blocks, and the obtained metal blocks are placed in an electric arc furnace for smelting. After the smelting is completed, water quenching is performed to obtain alloy particles. The nickel sulfate concentration of the water quenching liquid is 100g / L, and the flow rate of the water quenching liquid is 5m / s. The obtained alloy particles are then carbonyl synthesized, and the obtained carbonyl nickel enters the subsequent decomposition process to prepare carbonyl nickel powder for nickel sulfate; the obtained carbonyl slag is hydraulically classified. The pressure of the carbonyl synthesis is controlled at 9.0MPa, the temperature is controlled at 250±5℃, and the decomposition temperature of the carbonyl nickel is controlled at 180-300℃; the water flow rate of the hydraulic classification is 10m / s.

[0026] Finally, the obtained hydraulically classified heavy components are mixed with graphite powder, pressed into a mass, and placed in a muffle furnace for reduction roasting to obtain a Cr-Mo-Nb alloy; the particle size of the graphite powder does not exceed 0.1 mm, the mass percentage of the graphite powder is 5%, and the reduction roasting temperature is controlled at 1280±5°C.

[0027] According to the test, the mass content of oxygen in the Cr-Mo-Nb alloy prepared in this embodiment is 12.0 ppm, the mass content of nitrogen is 11.0 ppm, the mass content of C is 1.1%, the mass content of Mo is 25.0%, the mass content of Nb is 11.9%, and the balance is Cr and unavoidable impurities. The alloy can be used for vacuum induction melting of nickel-based alloy K418A and nickel-based alloy K418B.

[0028] Embodiment 4, First, the nickel-based alloy K418A, nickel-based alloy K418B and nickel-based alloy K418C slag materials are mixed and briquette. The obtained metal block material is placed in an electric arc furnace for smelting. After the smelting is completed, it is water quenched to obtain alloy particles. The nickel sulfate concentration of the water quenching liquid is 100g / L, and the flow rate of the water quenching liquid is 5m / s. The obtained alloy particles are then carbonyl synthesized, and the obtained carbonyl nickel enters the subsequent decomposition process to prepare carbonyl nickel powder for nickel sulfate; the obtained carbonyl slag is hydraulically classified. The pressure of carbonyl synthesis is controlled at 9.0MPa, the temperature is controlled at 250±5℃, and the decomposition temperature of carbonyl nickel is controlled at 180-300℃; the water flow rate of hydraulic classification is 10m / s.

[0029] Finally, the hydraulically classified heavy components obtained in the process are mixed with graphite powder, pressed into a mass, and placed in a muffle furnace for reduction roasting to obtain a Cr-Mo-Nb alloy; the hydraulically classified light components can be used for the preparation of building materials. The particle size of the graphite powder does not exceed 0.1 mm, the mass percentage of the graphite powder is 5%, and the reduction roasting temperature is controlled at 1280±5℃.

[0030] According to the test, the mass content of oxygen in the Cr-Mo-Nb alloy prepared in this embodiment is 11.5ppm, the mass content of nitrogen is 11.4ppm, the mass content of C is 1.0%, the mass content of Mo is 22.4%, the mass content of Nb is 9.3%, and the balance is Cr and unavoidable impurities. The alloy can be used for vacuum induction melting of nickel-based alloy K418A, nickel-based alloy K418B and nickel-based alloy K418C.

[0031] The Cr-Mo-Nb alloy prepared by the present invention has high purity and low oxygen and nitrogen content, is beneficial to the control of segregation and slag in the vacuum induction melting process of casting high-temperature alloys K418A, K418B, and K418C, and improves the quality of nickel-based alloy K418A, K418B, and K418C alloy products. At the same time, nickel in K418A, K418B, and K418C alloy slag is effectively recovered and can be directly used for the preparation of nickel powder for nickel sulfate.

Claims

1. A Cr-Mo-Nb alloy, characterized in that: The chemical composition and mass percentage of the alloy are: Mo: 22% to 26%, Nb: 9% to 13%, C≤2%, and the remainder is Cr and unavoidable impurity elements.

2. A method for producing a Cr-Mo-Nb alloy according to claim 1, characterized in that: The steps include: A. One or more of the nickel-based alloy K418A, K418B, and K418C slags are subjected to briquetting to form alloy briquette; B. melting the alloy briquette, and quenching the smelted alloy with a nickel sulfate solution to generate alloy particles; C. subjecting the alloy particles to carbonyl synthesis treatment to obtain carbonyl nickel and carbonyl slag, and subjecting the carbonyl slag to hydraulic classification to separate the carbonyl slag into light component materials and heavy component materials; D. The heavy component material after hydraulic classification and graphite powder are mixed, pressed into agglomerates, and reduction roasted to obtain Cr-Mo-Nb alloy.

3. The method for producing a Cr-Mo-Nb alloy according to claim 2, characterized in that: In step B, the concentration of the nickel sulfate solution is 1-100 g / L, and the flow rate of the water quenching liquid is 0.1-5 m / s.

4. The method for producing a Cr-Mo-Nb alloy according to claim 2, characterized in that: In step C, the synthesis pressure is 1-9 MPa and the temperature is ≤250°C.

5. The method for producing a Cr-Mo-Nb alloy according to claim 4, characterized in that: In step C, the water flow velocity of the hydraulic classification is 1-10 m / s.

6. The method for producing a Cr-Mo-Nb alloy according to claim 5, characterized in that: In step C, the carbonyl nickel obtained after carbonylation is decomposed to generate carbonyl nickel powder, which can be directly used to prepare the nickel sulfate solution used in step B. The decomposition temperature is 180-300°C.

7. The method for producing a Cr-Mo-Nb alloy according to claim 2, characterized in that: In step D, the particle size of graphite powder is ≤0.1 mm, the mass percentage of graphite powder is ≤5%, and the reduction roasting temperature is 850-1280°C.

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