A method for producing a cu-mn alloy by aluminothermic reduction-electromagnetic casting

Abstract

The application provides a method for preparing CuMn alloy by aluminum thermal reduction-electromagnetic casting, and belongs to the field of copper alloy preparation. The method comprises the following steps: preparing raw materials CuO, MnO2 powder, Al powder, CaO and KClO3, and adding CaO for slagging and 0-5% KClO3 as a heating agent when the raw materials are proportioned according to the mass of the required CuMn alloy; adding the mixture into a reaction furnace in batches to obtain WCu alloy melt and Al2O3-CaO reduction smelting slag; preparing calcium aluminate cement clinker from the obtained Al2O3-CaO smelting slag; and obtaining homogeneous CuMn alloy ingot after high-temperature mutual-solubility CuMn alloy melt is stirred in an electromagnetic field and cooled and solidified. The application utilizes the heat released by the reaction and does not need additional heat supply, and the preparation is carried out in a non-vacuum environment without a high vacuum degree. The electromagnetic stirring makes B single elements uniformly and dispersedly distributed in the Cu matrix, and water cooling and solidification effectively solves the segregation problem. The calcium aluminate slag generated by the application can be used to prepare calcium aluminate cement clinker, and the clean production of CuMn alloy is realized.

Description

TECHNICAL FIELD

[0001] The application belongs to the field of copper alloy preparation, and particularly relates to a method for preparing CuMn alloy by aluminothermic reduction-electromagnetic casting. BACKGROUND

[0002] Copper-manganese alloy is a basic material for making resistance elements in electronic instruments, measuring instruments and other industrial devices. As a resistance alloy material, it has the characteristics of small resistance, low temperature coefficient, low thermoelectric potential to copper, high stability of resistance and high resistivity, and can be made into powder, wire, foil, sheet, strip, rod, tube and other shapes. It is mainly used for making standard resistors, shunts, precision or ordinary resistance elements, high-grade voltage, current, bridge, potential difference meter and other precision resistance elements of instruments and meters, and is more suitable for making resistance elements of standard resistors for reference.

[0003] At present, high-end manganese-copper alloys on the domestic market are obtained by import, and domestic production is mainly carried out by non-vacuum melting and vacuum induction melting process. Application No. 201910797951.9 uses CuNi20 and CuMn50 intermediate alloy as raw material to prepare CuMn25Ni10 alloy by vacuum induction melting method; application No. 202211226905.1 uses electrolytic copper plate, electrolytic nickel plate and electrolytic manganese plate as raw material to prepare powder by gas atomization method, and then prepares CuMn12Ni3 by pressing, sintering, drawing and heat treatment. However, the above-mentioned patents use high-purity Cu, Mn and Ni as raw materials, which increases the cost of raw materials, and the process is complicated with high vacuum requirement. Therefore, how to reduce the production cost of the existing production technology and prepare copper-manganese alloy with performance equivalent to or better than commercial alloy to obtain good economic benefit is the research direction of CuMn alloy. SUMMARY

[0004] The application is implemented in the following way: CuO, MnO2 powder, Al powder, CaO and KClO3 are prepared, and when the mass of the required CuMn alloy is prepared, CaO is added for slagging, and 0-5% KClO3 is added as a heating agent; the mixture is added to the reaction furnace in batches to obtain WCu alloy melt and Al2O3-CaO reduction smelting slag; the obtained Al2O3-CaO smelting slag is directly prepared into calcium aluminate cement clinker by overflow slagging and water quenching; and the high-temperature mutual-soluble CuMn alloy melt is cooled and solidified under electromagnetic field stirring and circulating water cooling to obtain homogeneous CuMn alloy ingot.

[0005] A method for preparing CuMn alloy by aluminothermic reduction-electromagnetic casting is carried out in the following steps:

[0006] (1) CuO, MnO2 as raw material, Al powder as reducing agent, CaO as slagging agent, KClO3 as heating agent, after drying, mix well in the mixer to obtain the mixture;

[0007] (2) the mixture is added into the aluminothermic reduction reaction furnace in batches, and the mixture undergoes continuous reduction reaction to obtain CuMn alloy melt and Al2O3-CaO reduction slag;

[0008] (3) the CuMn alloy melt is fully inter-dissolved by electromagnetic stirring;

[0009] (4) the high-temperature inter-dissolved CuMn alloy melt is solidified to obtain homogeneous CuMn alloy ingot.

[0010] Further, in step (1), the mass ratio of CuO:MnO2:Al:CaO is 1:(0.15-0.75):(0.2-0.7):(0.1-0.4), and the amount of KClO3 added is 0-5% of the total mass of the reaction material, so that the Mn content in the alloy is 10%-40%, and the melting point of the Al2O3-CaO reduction slag is between 1400°C and 1600°C.

[0011] Further, in step (1), the drying temperature is 150°C, and the time is 24h.

[0012] Further, in step (2), Mg powder is added to the surface layer of the mixture to ignite the aluminothermic reduction reaction.

[0013] Further, in step (2), the Al2O3-CaO reduction slag is prepared into calcium aluminate cement clinker by overflow slagging and water quenching, and the amount of CaO in the reduction slag is added according to the cement grade.

[0014] Further, in step (3), the stirring frequency of electromagnetic stirring is 10-60Hz, and the stirring time is 10-20min.

[0015] Further, in step (4), the solidification is carried out in a circulating water cooling mold, and the solidification speed is 10-15℃ / s.

[0016] The beneficial effects of the present application are:

[0017] (1) Compared with vacuum melting, the method of the present application uses cheap CuO and MnO2 raw materials, utilizes the heat released by the reaction itself without the need for additional heat supply, has low production cost, and does not require high vacuum degree for preparation in a non-vacuum environment;

[0018] (2) Compared with traditional metallurgical methods, the process uses electromagnetic stirring to make B single atoms uniformly dispersed in the Cu matrix, and water cooling solidification effectively solves the segregation problem.

[0019] (3) The calcium aluminate slag generated by the present application can be used to prepare calcium aluminate cement clinker, and realize clean production of CuMn alloy;

[0020] (4) The CaO addition has two effects: one is to adjust the melting point of the Al2O3-CaO reduction slag to be between 1400℃ and 1600℃, and the other is to regulate the grade of the calcium aluminate cement clinker prepared by overflow slagging and water quenching. DETAILED DESCRIPTION

[0021] The technical solutions in the embodiments of the present application will be clearly and completely described below in combination with the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor fall within the scope of protection of the present application.

[0022] Embodiment 1

[0023] (1) According to the composition of the CuMn15 gold ingot to be prepared, CuO, MnO2, Al powder, CaO and KClO3 are prepared, and the required CuO, MnO2 and CaO for the reaction are placed in an oven at 150℃ for 24h.

[0024] (2) When the ingredients are mixed, the ingredients are mixed in a mass ratio of CuO:MnO2:Al:CaO = 1:0.22:0.32:0.16, and 1% KClO3 is added into the mixing tank according to the percentage of the total mass of the reactants, and then mixed for 10min on a ball mill. Part of the mixed material is placed in an aluminothermic reduction reaction furnace, Mg powder is added to the surface layer to ignite the aluminothermic reduction reaction, and the remaining material is continuously added in batches. Through the aluminothermic reduction reaction, CuMn alloy melt and Al2O3-CaO reduction slag are obtained,

[0025] (3) The electromagnetic stirring device and the circulating water cooling device are turned on, and the gold slag is separated under the action of electromagnetic stirring. The electromagnetic stirring frequency is 18Hz, the stirring time is 10min, and the cooling rate is 10℃ / s. The upper Al2O3-CaO reduction slag is discharged by the overflow slagging method to prepare calcium aluminate cement clinker; and the lower CuMn alloy melt is rapidly solidified into CuMn15 alloy ingot under the action of water cooling. The Mn content in the alloy is 13-16%.

[0026] Embodiment 2

[0027] (1) According to the composition of the CuMn20 gold ingot to be prepared, CuO, MnO2, Al powder, CaO and KClO3 are prepared, and the required CuO, MnO2 and CaO for the reaction are placed in an oven at 150℃ for 24h.

[0028] (2) Mixed ingredients were prepared according to the mass ratio of CuO:MnO2:Al:CaO = 1:0.32:0.36:0.18, and 2% KClO3 was added into the mixed ingredients in the mixing tank, and the mixed ingredients were mixed in a ball mill for 20 min. Part of the mixed ingredients was placed in an aluminothermic reduction reactor, Mg powder was added to the surface layer to ignite the aluminothermic reduction reaction, and the remaining ingredients were continuously added in batches. The CuMn alloy melt and Al2O3-CaO reduction slag were obtained by aluminothermic reduction reaction,

[0029] (3) The electromagnetic stirring device and the circulating water cooling device were turned on, and the gold slag was separated under the action of electromagnetic stirring. The electromagnetic stirring frequency was 20 Hz, the stirring time was 15 min, and the cooling rate was 12 ℃ / s. The upper layer of Al2O3-CaO reduction slag was discharged by overflow slagging method to prepare calcium aluminate cement clinker. The lower part of the CuMn alloy melt was rapidly solidified into CuMn20 alloy ingot under the action of water cooling. The Mn content in the alloy was 19-21%.

[0030] Example 3

[0031] (1) CuO, MnO2, Al powder, CaO and KClO3 were prepared according to the composition of the CuMn25 gold ingot to be prepared. CuO, MnO2 and CaO required for the reaction were placed in an oven at 150°C and baked for 24 h.

[0032] (2) Mixed ingredients were prepared according to the mass ratio of CuO:MnO2:Al:CaO = 1:0.42:0.40:0.21, and 3% KClO3 was added into the mixed ingredients in the mixing tank, and the mixed ingredients were mixed in a ball mill for 30 min. Part of the mixed ingredients was placed in an aluminothermic reduction reactor, Mg powder was added to the surface layer to ignite the aluminothermic reduction reaction, and the remaining ingredients were continuously added in batches. The CuMn alloy melt and Al2O3-CaO reduction slag were obtained by aluminothermic reduction reaction,

[0033] (3) The electromagnetic stirring device and the circulating water cooling device were turned on, and the gold slag was separated under the action of electromagnetic stirring. The electromagnetic stirring frequency was 22 Hz, the stirring time was 18 min, and the cooling rate was 13 ℃ / s. The upper layer of Al2O3-CaO reduction slag was discharged by overflow slagging method to prepare calcium aluminate cement clinker. The lower part of the CuMn alloy melt was rapidly solidified into CuMn25 alloy ingot under the action of water cooling. The Mn content in the alloy was 23-26%.

[0034] Example 4

[0035] (1) CuO, MnO2, Al powder, CaO and KClO3 were prepared according to the composition of CuMn30 gold ingot to be prepared, and CuO, MnO2 and CaO required for the reaction were placed in an oven at 150°C for 24h.

[0036] (2) When the ingredients were mixed, the ingredients were prepared in a mass ratio of CuO:MnO2:Al:CaO = 1:0.54:0.45:0.23, and 4% KClO3 was added to the raw materials according to the percentage of the total mass of the reactants, and mixed in a mixing tank for 50 min on a ball mill. Part of the mixed material was placed in an aluminothermic reduction reactor, Mg powder was added to the surface layer to ignite the aluminothermic reduction reaction, and the remaining material was continuously added in batches, and CuMn alloy melt and Al2O3-CaO reduction slag were obtained by aluminothermic reduction,

[0037] (3) The electromagnetic stirring device and the circulating water cooling device were turned on, and the gold slag was separated under the action of electromagnetic stirring, the electromagnetic stirring frequency was 23Hz, the stirring time was 20min, and the cooling rate was 14°C / s. The upper Al2O3-CaO reduction slag was discharged by overflow slagging method to prepare calcium aluminate cement clinker; the lower part of the CuMn alloy melt was rapidly solidified under the action of water cooling to obtain CuMn30 alloy ingot, and the Mn content in the alloy was 28-32%.

[0038] Example 5

[0039] (1) CuO, MnO2, Al powder, CaO and KClO3 were prepared according to the composition of CuMn30 gold ingot to be prepared, and CuO, MnO2 and CaO required for the reaction were placed in an oven at 150°C for 24h.

[0040] (2) When the ingredients were mixed, the ingredients were prepared in a mass ratio of CuO:MnO2:Al:CaO = 1:0.68:0.51:0.26, and 5% KClO3 was added to the raw materials according to the percentage of the total mass of the reactants, and mixed in a mixing tank for 60 min on a ball mill. Part of the mixed material was placed in an aluminothermic reduction reactor, Mg powder was added to the surface layer to ignite the aluminothermic reduction reaction, and the remaining material was continuously added in batches, and CuMn alloy melt and Al2O3-CaO reduction slag were obtained by aluminothermic reduction,

[0041] (3) The electromagnetic stirring device and the circulating water cooling device were turned on, and the gold slag was separated under the action of electromagnetic stirring, the electromagnetic stirring frequency was 23Hz, the stirring time was 20min, and the cooling rate was 14°C / s. The upper Al2O3-CaO reduction slag was discharged by overflow slagging method to prepare calcium aluminate cement clinker; the lower part of the CuMn alloy melt was rapidly solidified under the action of water cooling to obtain CuMn30 alloy ingot, and the Mn content in the alloy was 28-32%.

Claims

1. A method for preparing CuMn alloy by aluminothermic reduction-electromagnetic casting, characterized in that, Follow these steps: (1) Using CuO and MnO2 as raw materials, Al powder as reducing agent, CaO as slag-forming agent, and KClO3 as exothermic agent, the mixture is thoroughly mixed in a mixer after drying to obtain a mixture. (2) The mixture is added to the aluminothermic reduction reactor in batches, and the mixture undergoes a continuous reduction reaction to obtain CuMn alloy melt and Al2O3-CaO reduction slag; (3) Electromagnetic stirring promotes full mutual solubility of CuMn alloy melt; (4) The high-temperature miscible CuMn alloy melt is solidified to obtain a homogeneous CuMn alloy ingot. In step (1), the CuO:MnO2:Al:CaO ratio is 1:(0.15~0.75):(0.2~0.7):(0.1~0.4), and the amount of KClO3 added is 1~5% of the total mass of the reactants, so that the Mn content in the alloy is 10%~40%, and the melting point of the Al2O3-CaO reduction slag is between 1400℃ and 1600℃.

2. The method for preparing CuMn alloy by aluminothermic reduction-electromagnetic casting according to claim 1, characterized in that, The drying temperature in step (1) is 150℃ and the drying time is 24h.

3. The method for preparing CuMn alloy by aluminothermic reduction-electromagnetic casting according to claim 1, characterized in that, The reduction reaction in step (2) is as follows: Mg powder is added to the surface of the mixture to ignite the aluminothermic reduction reaction.

4. The method for preparing CuMn alloy by aluminothermic reduction-electromagnetic casting according to claim 1, characterized in that, In step (2), the Al2O3-CaO reducing slag is quenched by overflow discharge to prepare calcium aluminate cement clinker. The amount of CaO in the reducing slag is added according to the cement grade.

5. The method for preparing CuMn alloy by aluminothermic reduction-electromagnetic casting according to claim 1, characterized in that, The electromagnetic stirring frequency in step (3) is 10~60Hz and the stirring time is 10~20min.

6. The method for preparing CuMn alloy by aluminothermic reduction-electromagnetic casting according to claim 1, characterized in that, The solidification described in step (4) is carried out in a circulating water-cooled mold at a solidification rate of 10~15℃ / s.