High-purity copper-manganese alloy cast ingot and preparation method thereof

Abstract

The invention provides a high-purity copper-manganese alloy cast ingot and a preparation method thereof. The preparation method comprises the following steps: (1) pretreating a raw material copper and a raw material manganese to obtain treated copper particles and manganese particles; (2) the copper particles obtained in the step (1) are subjected to melting treatment to obtain liquid copper, then manganese particles and the liquid copper are mixed for pre-melting degassing, and first alloy liquid is obtained; (3) manganese particles are added into the first alloy liquid obtained in the step (2) at a controlled speed for alloying treatment, and second alloy liquid is obtained after vacuum purification and refining; and (4) the second alloy liquid obtained in the step (3) is subjected to casting treatment, and the high-purity copper-manganese alloy cast ingot is obtained. According to the method, through the multi-stage control vacuum smelting process of pre-degassing, slow alloying, vacuum purification, speed-controlled solidification and the like, the purity, the component uniformity and the structure compactness of the copper-manganese alloy are effectively improved, and batch, stable and reproducible industrial preparation is achieved.

Description

Technical Field

[0001] This invention belongs to the field of non-ferrous metal alloy technology, specifically relating to a high-purity copper-manganese alloy ingot and its preparation method. Background Technology

[0002] Copper-manganese alloys are important electronic and sputtering materials. Due to the ability of manganese in a copper matrix to effectively improve the mechanical properties and resistivity of the alloy, they are widely used in high-end fields such as semiconductors, display panels, and magnetic materials. With the continuous upgrading of downstream industry technologies, increasingly stringent requirements are being placed on the purity, microstructure density, and compositional uniformity of copper-manganese alloy ingots. These performance indicators directly affect the reliability and service life of end devices.

[0003] Currently, the industrial production of copper-manganese alloy ingots commonly employs a single-step medium-frequency vacuum induction melting process. A typical flow of this process involves adding copper and manganese raw materials into a vacuum furnace at once, evacuating to a set vacuum level, and then melting. Once the alloy melt is formed, the ingot is directly poured out. Representative companies using this process include some target material suppliers and military material manufacturers. While the technology offers a degree of controllability, it has significant limitations in meeting the demands for high-purity and high-consistency products.

[0004] Specifically, the existing single-step melting process has the following shortcomings: (1) During the one-time alloying process, manganese is prone to violent volatilization due to high temperature, and is also prone to oxidation when exposed to the melting environment. In addition, due to the difference in density and melting point between copper and manganese, element segregation is very likely to occur, resulting in poor uniformity of alloy composition, which makes it difficult to meet the strict requirements of high-precision applications for the range of composition fluctuations; (2) Gases and non-metallic inclusions are difficult to remove completely. In particular, after the addition of manganese raw materials, the oxide layer on its surface or the impurities it carries are easily encapsulated by the melt, and are difficult to fully volatilize or float in the vacuum environment of single-step melting, resulting in residual gases in the alloy. (e.g., hydrogen, oxygen, nitrogen) and inclusions (e.g., oxides, silicates) exceed the standard, reducing the purity of the material; (3) The cooling process lacks precise control, and the melt cools unevenly in the mold, which easily forms coarse grains or directional columnar structures, resulting in uneven mechanical properties of the ingot. In subsequent processing, defects such as cracking and deformation are likely to occur, affecting the yield of processed materials; (4) The process lacks a phased temperature and pressure control design. The temperature and vacuum control window of the entire melting process is narrow, and it is extremely sensitive to the slight fluctuations in operating parameters, resulting in large performance differences between different batches of products, making it difficult to achieve stability and consistency in industrial production.

[0005] In summary, under industrial production conditions, relying solely on single-step vacuum induction melting or atmosphere-protected melting can no longer meet the high requirements of high-end fields for copper-manganese alloy ingots in terms of purity, microstructure density, and compositional uniformity. There is an urgent need for a new smelting process that can stably remove gas and non-metallic inclusions and precisely control the alloying process and solidification structure. Summary of the Invention

[0006] To address the shortcomings of existing technologies, the present invention aims to provide a high-purity copper-manganese alloy ingot and its preparation method. This invention utilizes a multi-stage controlled vacuum smelting process, specifically through pre-degassing, slow alloying, vacuum purification, and controlled-rate solidification, to effectively improve the purity, compositional uniformity, and microstructure density of the copper-manganese alloy, achieving batch, stable, and reproducible industrial production.

[0007] To achieve this objective, the present invention adopts the following technical solution:

[0008] In a first aspect, the present invention provides a method for preparing a high-purity copper-manganese alloy ingot, the method comprising the following steps:

[0009] (1) Pre-treat the raw copper and raw manganese to obtain treated copper and manganese particles;

[0010] (2) The copper particles obtained in the melting process (1) are used to obtain liquid copper. Then, manganese particles and the liquid copper are mixed and pre-melted to remove gas, resulting in the first alloy liquid.

[0011] (3) Add manganese particles to the first alloy liquid obtained in step (2) at a controlled rate for alloying treatment, and then obtain the second alloy liquid after vacuum purification and refining.

[0012] (4) The second alloy liquid obtained in step (3) is cast to obtain the high-purity copper-manganese alloy ingot.

[0013] This invention effectively improves the purity, compositional uniformity, and microstructure density of copper-manganese alloys through a multi-stage process including pre-degassing, slow alloying, vacuum purification, and controlled-speed solidification, enabling batch, stable, and reproducible industrial preparation.

[0014] As a preferred technical solution of the present invention, the purity of the raw material copper in step (1) is ≥99.9999%, for example, it can be 99.9999%, 99.99992%, 99.99994% or 99.99996%, etc., but is not limited to the listed values. Other unlisted values ​​within the range are also applicable.

[0015] Preferably, the purity of the raw material manganese in step (1) is ≥99.999%, for example, it can be 99.999%, 99.9992%, 99.9994%, 99.9996% or 99.9998%, etc., but is not limited to the listed values. Other unlisted values ​​within the range are also applicable.

[0016] Preferably, the pretreatment in step (1) includes a drying process.

[0017] Preferably, the drying temperature is 70-90°C, for example, 70°C, 74°C, 78°C, 82°C, 86°C or 90°C, but is not limited to the listed values. Other unlisted values ​​within the range are also applicable.

[0018] Preferably, the drying time is 12 to 20 hours, for example, 12 hours, 13 hours, 14 hours, 15 hours, 16 hours, 17 hours, 18 hours, 19 hours or 20 hours, but is not limited to the listed values. Other unlisted values ​​within the range are also applicable.

[0019] This invention achieves a certain dehumidification and cleaning effect on raw materials copper and manganese by reasonably controlling the temperature of the drying process. If the temperature of the drying process is too high, it will cause the manganese to oxidize or burn off, while if the temperature is too low, the moisture in the raw materials will not be completely removed, which will easily produce pores or inclusions during the smelting process.

[0020] As a preferred technical solution of the present invention, the melting temperature in step (2) is 1050 to 1100°C, for example, it can be 1050°C, 1060°C, 1070°C, 1080°C, 1090°C or 1100°C, etc., but is not limited to the listed values. Other unlisted values ​​within the range are also applicable.

[0021] Preferably, the mass ratio of copper particles to manganese particles in step (2) is 19:0.8 to 1.2, for example, it can be 19:0.8, 19:0.9, 19:1, 19:1.1 or 19:1.2, etc., but is not limited to the listed values. Other unlisted values ​​within the range are also applicable.

[0022] As a preferred technical solution of the present invention, the temperature of pre-melting and degassing in step (2) is 1020 to 1070°C, for example, it can be 1020°C, 1030°C, 1040°C, 1050°C, 1060°C or 1070°C, but is not limited to the listed values. Other unlisted values ​​within the range are also applicable.

[0023] Preferably, the vacuum degree of the pre-melting degassing in step (2) is 5×10⁻⁶. -3 ~1×10 -4 Mbar, for example, could be 5×10 -3 Mbar, 3×10 -3 Mbar, 1×10 -3 Mbar, 8×10 -4 Mbar, 5×10 -4 Mbar, 2×10 -4 Mbar or 1×10 -4Mbar, etc., but not limited to the listed values, and other unlisted values ​​within the range also apply.

[0024] Preferably, the pre-melting and degassing time in step (2) is 1 to 2 hours, for example, it can be 1 hour, 1.2 hours, 1.4 hours, 1.6 hours, 1.8 hours or 2 hours, but is not limited to the listed values. Other unlisted values ​​within the range are also applicable.

[0025] This invention helps remove oxygen and hydrogen impurities from the alloy and improves the purity of the alloy ingot by using precise vacuum environment and temperature control during the pre-melting and degassing process. More specifically, if the pre-melting and degassing temperature is too high, copper will volatilize, causing the composition to deviate from the design range. If the temperature is too low, the melt fluidity will be insufficient and the degassing will be incomplete, resulting in porosity defects in subsequent casting. Therefore, the temperature needs to be controlled within a suitable range to balance degassing efficiency and composition stability.

[0026] As a preferred technical solution of the present invention, the addition rate of manganese particles in step (3) is 0.6 to 1.0 kg / min, for example, it can be 0.6 kg / min, 0.7 kg / min, 0.8 kg / min, 0.9 kg / min or 1.0 kg / min, but is not limited to the listed values. Other unlisted values ​​within the range are also applicable.

[0027] Preferably, the amount of manganese particles added in step (3) is 5 to 5.5% of the mass of the first alloy liquid, for example, it can be 5%, 5.1%, 5.2%, 5.3%, 5.4% or 5.5%, etc., but is not limited to the listed values. Other unlisted values ​​within the range are also applicable.

[0028] Preferably, the alloying temperature in step (3) is 1130 to 1170°C, for example, it can be 1130°C, 1135°C, 1140°C, 1145°C, 1150°C, 1160°C or 1170°C, but is not limited to the listed values. Other unlisted values ​​within the range are also used.

[0029] It is worth noting that the present invention flexibly adjusts the addition rate of manganese particles according to the needs of the alloy to make the alloy composition uniform. If the addition rate of manganese particles is too fast, it is easy to cause local overheating, violent reaction and increased oxidation inclusions, and even lead to composition fluctuations. If the addition rate is too slow, it will reduce the diffusion and dissolution efficiency of manganese in the melt, prolong the smelting time and affect the uniformity of the alloy composition. Therefore, it is necessary to control it within a suitable rate range to ensure the stability of the melt composition and the uniformity of the structure.

[0030] As a preferred technical solution of the present invention, the temperature of vacuum purification and refining in step (3) is 1200-1300℃, for example, it can be 1200℃, 1220℃, 1240℃, 1260℃, 1280℃ or 1300℃, etc., but is not limited to the listed values. Other unlisted values ​​within the range are also applicable.

[0031] Preferably, the vacuum degree of the vacuum purification and refining in step (3) is 1×10⁻⁶. -5 ~1×10 -6 Mbar, for example, could be 1×10 -5 Mbar, 8×10 -6 Mbar, 6×10 -6 Mbar, 4×10 -6 Mbar, 2×10 -6 Mbar or 1×10 -6 Mbar, etc., but not limited to the listed values, and other unlisted values ​​within the range also apply.

[0032] Preferably, the vacuum purification and refining time in step (3) is 2.5 to 3.5 hours, for example, it can be 2.5 hours, 2.7 hours, 2.9 hours, 3.1 hours, 3.3 hours or 3.5 hours, but is not limited to the listed values. Other unlisted values ​​within the range are also applicable.

[0033] It is worth noting that the present invention utilizes a vacuum purification and refining process to further remove impurities from the alloy and improve the alloy purity. If the refining temperature is too high, it will lead to increased volatilization of manganese and an increase in oxidized inclusions. If the temperature is too low, it will lead to insufficient melt fluidity and incomplete floating of inclusions, thereby reducing the refining effect. Therefore, the refining temperature needs to be controlled within a reasonable range to balance the removal of impurities and the stability of the composition.

[0034] As a preferred technical solution of the present invention, the casting process in step (4) includes: pouring the second alloy liquid into a water-cooled mold for solidification treatment, and then performing air cooling treatment.

[0035] Preferably, the vacuum degree of the casting process is 10. -2 ~10 -3 Mbar, for example, can be 10 -3 Mbar, 2×10 - 3 Mbar, 4×10 -3 Mbar, 6×10 -3 Mbar, 8×10 -3 Mbar or 10 -2 Mbar, etc., but not limited to the listed values, and other unlisted values ​​within the range also apply.

[0036] Preferably, the temperature of the second alloy liquid is 1180 to 1230°C, for example, it can be 1180°C, 1190°C, 1200°C, 1210°C, 1220°C or 1230°C, but is not limited to the listed values. Other values ​​within the range that are not listed are also applicable.

[0037] Preferably, the pouring speed is 0.6 to 0.8 kg / s, for example, it can be 0.6 kg / s, 0.64 kg / s, 0.68 kg / s, 0.72 kg / s, 0.76 kg / s or 0.8 kg / s, etc., but is not limited to the listed values. Other unlisted values ​​within the range are also applicable.

[0038] Preferably, the cooling rate of the solidification treatment is 100 to 1000 K / s, for example, it can be 100 K / s, 200 K / s, 400 K / s, 600 K / s, 800 K / s or 1000 K / s, etc., but is not limited to the listed values. Other unlisted values ​​within the range are also applicable.

[0039] In this invention, cooling water is used for solidification treatment. By controlling the cooling rate, the grain density of the alloy can be improved. If the cooling rate is too fast, it is easy to cause thermal stress concentration, resulting in cracks or segregation. If the cooling rate is too slow, it may cause grain coarsening, shrinkage cavities and compositional agglomeration. Therefore, the cooling rate needs to be controlled within a reasonable range to obtain an ingot with a dense structure and uniform composition.

[0040] Preferably, the final temperature of the solidification treatment is 600-700℃, for example, it can be 600℃, 620℃, 640℃, 660℃, 680℃ or 700℃, but is not limited to the listed values. Other unlisted values ​​within the range are also applicable.

[0041] Preferably, the cooling rate of the air cooling treatment is 1 to 10 K / s, for example, it can be 1 K / s, 2 K / s, 4 K / s, 6 K / s, 8 K / s or 10 K / s, etc., but is not limited to the listed values. Other unlisted values ​​within the range are also applicable.

[0042] It is worth noting that the casting process described in this invention also includes surface treatment, which includes pickling and polishing processes performed sequentially.

[0043] Preferably, the acid used for pickling includes sulfuric acid.

[0044] As a preferred embodiment of the present invention, the method for preparing high-purity copper-manganese alloy ingots provided in the first aspect of the present invention includes the following steps:

[0045] (1) The raw copper and raw manganese were dried at 70-90℃ for 12-20h to obtain the processed copper and manganese particles.

[0046] (2) The copper particles obtained in step (1) are melted at 1050-1100℃ to obtain liquid copper. Then, manganese particles and the liquid copper are mixed and pre-melted to remove gas, resulting in a first alloy liquid.

[0047] The mass ratio of copper particles to manganese particles is 19:0.8 to 1.2.

[0048] The pre-melting and degassing temperature is 1020–1070℃, and the vacuum degree is 5×10⁻⁶. -3 ~1×10 -4 Mbar, duration 1-2 hours;

[0049] (3) Add manganese particles to the first alloy liquid obtained in step (2) at a controlled rate for alloying treatment, and then obtain the second alloy liquid after vacuum purification and refining.

[0050] The manganese particles are added at a rate of 0.6–1.0 kg / min, and the alloying temperature is 1130–1170 °C.

[0051] The vacuum purification and refining temperature is 1200–1300℃, and the vacuum degree is 1×10⁻⁶. -5 ~1×10 -6 Mbar, duration 2.5–3.5h;

[0052] (4) In 10 -2 ~10 -3 Under Mbar vacuum, the second alloy liquid at a temperature of 1180-1230℃ is poured into a water-cooled mold for solidification, and then air-cooled to obtain the high-purity copper-manganese alloy ingot.

[0053] The pouring speed is 0.6–0.8 kg / s;

[0054] The cooling rate of the solidification treatment is 100-1000 K / s, and the final temperature is 600-700℃; the cooling rate of the air cooling treatment is 1-10 K / s.

[0055] Secondly, the present invention provides a high-purity copper-manganese alloy ingot obtained by the preparation method provided in the first aspect, wherein the manganese content in the high-purity copper-manganese alloy ingot is 4.5 to 5.5 wt%, for example, it can be 4.5 wt%, 4.7 wt%, 4.9 wt%, 5.1 wt%, 5.3 wt%, or 5.5 wt%, etc., but is not limited to the listed values, and other unlisted values ​​within the range are also applicable.

[0056] The high-purity copper-manganese alloy ingot described in this invention can be used for precision resistive materials or target materials.

[0057] The numerical range described in this invention includes not only the point values ​​listed above, but also any point values ​​within the numerical ranges not listed above. Due to space limitations and for the sake of brevity, this invention will not exhaustively list all the specific point values ​​included in the range.

[0058] Compared with the prior art, the present invention has the following beneficial effects:

[0059] This invention utilizes a multi-stage vacuum smelting process, including pre-degassing, slow alloying, vacuum purification, and controlled-speed solidification, to effectively improve the purity, compositional uniformity, and microstructure density of copper-manganese alloys, enabling batch, stable, and reproducible industrial production. Detailed Implementation

[0060] The technical solution of the present invention will be further illustrated below through specific embodiments. Those skilled in the art should understand that the embodiments described are merely illustrative of the present invention and should not be construed as limiting the invention in any way.

[0061] Example 1

[0062] This embodiment provides a high-purity copper-manganese alloy ingot, wherein the manganese content in the high-purity copper-manganese alloy ingot is 5 wt%;

[0063] The preparation method of the high-purity copper-manganese alloy ingot includes the following steps:

[0064] (1) The raw copper and raw manganese were dried at 80℃ for 18 hours to obtain the processed copper and manganese particles.

[0065] (2) The copper particles obtained in step (1) are melted at 1075°C to obtain liquid copper. Then, manganese particles and the liquid copper are mixed and pre-melted to remove gas, resulting in a first alloy liquid.

[0066] The mass ratio of copper particles to manganese particles is 19:1;

[0067] The pre-melting and degassing temperature is 1050℃, and the vacuum degree is 1×10⁻⁶. -3 Mbar, time is 1.5h;

[0068] (3) Add manganese particles to the first alloy liquid obtained in step (2) at a controlled rate for alloying treatment, and then obtain the second alloy liquid after vacuum purification and refining.

[0069] The manganese particles were added at a rate of 0.8 kg / min, and the alloying temperature was 1140°C.

[0070] The vacuum purification and refining temperature is 1250℃, and the vacuum degree is 5×10⁻⁶.-6 Mbar, duration is 3 hours;

[0071] (4) In 5×10 -3 Under Mbar vacuum, the second alloy liquid at 1200℃ is poured into a water-cooled mold for solidification, and then air-cooled to obtain the high-purity copper-manganese alloy ingot.

[0072] The pouring speed is 0.7 kg / s;

[0073] The cooling rate of the solidification treatment is 500 K / s, and the final temperature is 650℃; the cooling rate of the air cooling treatment is 5 K / s.

[0074] Example 2

[0075] This embodiment provides a high-purity copper-manganese alloy ingot, the preparation method of which includes the following steps:

[0076] (1) The raw copper and raw manganese were dried at 70℃ for 20h to obtain the processed copper and manganese particles.

[0077] (2) The copper particles obtained in step (1) are melted at 1050℃ to obtain liquid copper. Then, manganese particles and the liquid copper are mixed and pre-melted to remove gas, resulting in a first alloy liquid.

[0078] The mass ratio of copper particles to manganese particles is 19:0.8.

[0079] The pre-melting and degassing temperature is 1020℃, and the vacuum degree is 1×10⁻⁶. -4 Mbar, time is 2h;

[0080] (3) Add manganese particles to the first alloy liquid obtained in step (2) at a controlled rate for alloying treatment, and then obtain the second alloy liquid after vacuum purification and refining.

[0081] The manganese particles were added at a rate of 0.6 kg / min, and the alloying temperature was 1130°C.

[0082] The vacuum purification and refining temperature is 1200℃, and the vacuum degree is 1×10⁻⁶. -6 Mbar, time is 3.5h;

[0083] (4) In 10 -3 Under Mbar vacuum, the second alloy liquid at 1180℃ is poured into a water-cooled mold for solidification, and then air-cooled to obtain the high-purity copper-manganese alloy ingot.

[0084] The pouring speed is 0.6 kg / s;

[0085] The cooling rate of the solidification treatment is 100 K / s, and the final temperature is 700℃; the cooling rate of the air cooling treatment is 1 K / s.

[0086] Example 3

[0087] This embodiment provides a high-purity copper-manganese alloy ingot, the preparation method of which includes the following steps:

[0088] (1) The raw copper and raw manganese were dried at 90℃ for 12 hours to obtain the processed copper and manganese particles.

[0089] (2) The copper particles obtained in step (1) are melted at 1100℃ to obtain liquid copper. Then, manganese particles and the liquid copper are mixed and pre-melted to remove gas, resulting in a first alloy liquid.

[0090] The mass ratio of copper particles to manganese particles is 19:1.2.

[0091] The pre-melting and degassing temperature is 1070℃, and the vacuum degree is 5×10⁻⁶. -3 Mbar, time is 1 hour;

[0092] (3) Add manganese particles to the first alloy liquid obtained in step (2) at a controlled rate for alloying treatment, and then obtain the second alloy liquid after vacuum purification and refining.

[0093] The manganese particles were added at a rate of 0.6 kg / min, and the alloying temperature was 1170 °C.

[0094] The vacuum purification and refining temperature is 1300℃, and the vacuum degree is 1×10⁻⁶. -5 Mbar, time is 2.5h;

[0095] (4) In 10 -2 Under Mbar vacuum, the second alloy liquid at 1230℃ is poured into a water-cooled mold for solidification, and then air-cooled to obtain the high-purity copper-manganese alloy ingot.

[0096] The pouring speed is 0.8 kg / s;

[0097] The cooling rate of the solidification treatment is 1000 K / s, and the final temperature is 600℃; the cooling rate of the air cooling treatment is 10 K / s.

[0098] Example 4

[0099] This embodiment provides a high-purity copper-manganese alloy ingot, the preparation method of which differs from that of Embodiment 1 only in that:

[0100] In this embodiment, the addition rate of manganese particles in step (3) is adjusted to 0.4 kg / min.

[0101] Example 5

[0102] This embodiment provides a high-purity copper-manganese alloy ingot, the preparation method of which differs from that of Embodiment 1 only in that:

[0103] In this embodiment, the addition rate of manganese particles in step (3) is adjusted to 1.4 kg / min.

[0104] Example 6

[0105] This embodiment provides a high-purity copper-manganese alloy ingot, the preparation method of which differs from that of Embodiment 1 only in that:

[0106] In this embodiment, the temperature of the alloying treatment in step (3) is adjusted to 1100℃.

[0107] Example 7

[0108] This embodiment provides a high-purity copper-manganese alloy ingot, the preparation method of which differs from that of Embodiment 1 only in that:

[0109] In this embodiment, the temperature of the alloying treatment in step (3) is adjusted to 1200℃.

[0110] Example 8

[0111] This embodiment provides a high-purity copper-manganese alloy ingot, the preparation method of which differs from that of Embodiment 1 only in that:

[0112] In this embodiment, the vacuum purification and refining temperature in step (3) is 1100℃, and the vacuum degree is 4×10⁻⁶. -6 Mbar.

[0113] Example 9

[0114] This embodiment provides a high-purity copper-manganese alloy ingot, the preparation method of which differs from that of Embodiment 1 only in that:

[0115] In this embodiment, the vacuum purification and refining temperature in step (3) is 1400℃, and the vacuum degree is 3×10⁻⁶. -5 Mbar.

[0116] Example 10

[0117] This embodiment provides a high-purity copper-manganese alloy ingot, the preparation method of which differs from that of Embodiment 1 only in that:

[0118] In this embodiment, the cooling rate of the solidification process described in step (4) is adjusted to 50K / s.

[0119] Example 11

[0120] This embodiment provides a high-purity copper-manganese alloy ingot, the preparation method of which differs from that of Embodiment 1 only in that:

[0121] In this embodiment, the cooling rate of the solidification process described in step (4) is adjusted to 1100K / s.

[0122] Example 12

[0123] This embodiment provides a high-purity copper-manganese alloy ingot, the preparation method of which differs from that of Embodiment 1 only in that:

[0124] This embodiment omits the air cooling process described in step (4).

[0125] Comparative Example 1

[0126] This comparative example provides a high-purity copper-manganese alloy ingot, the preparation method of which differs from that of Example 1 only in that:

[0127] In this comparative example, step (2) is adjusted to: mixing copper and manganese particles and then performing a melting process, followed by pre-melting and degassing.

[0128] Comparative Example 2

[0129] This comparative example provides a high-purity copper-manganese alloy ingot, the preparation method of which differs from that of Example 1 only in that:

[0130] This comparative example omits the pre-melting and degassing described in step (2).

[0131] Comparative Example 3

[0132] This comparative example provides a high-purity copper-manganese alloy ingot, the preparation method of which differs from that of Example 1 only in that:

[0133] This comparative example adjusts the controlled addition of manganese particles in step (3) to a one-time addition of manganese particles.

[0134] Performance testing:

[0135] The purity and microstructure density of the copper-manganese alloy ingots provided in the above embodiments and comparative examples were tested, and the results are shown in Table 1.

[0136] Table 1

[0137]

[0138]

[0139] According to the data in Table 1:

[0140] (1) Comprehensive analysis of Examples 1-3 shows that the copper-manganese alloy prepared by the preparation method provided by the present invention has high purity, excellent microstructure and composition uniformity.

[0141] (2) Comprehensive analysis of Examples 1, 4-5 and Comparative Example 3 shows that the addition rate of manganese particles during the alloying process will affect the compositional uniformity of the alloy.

[0142] More specifically, if the addition rate of manganese particles is too high, it will lead to local overheating, violent reaction and increased oxidation inclusions, and even compositional fluctuations. If it is too low, it will reduce the diffusion and dissolution efficiency of manganese in the melt, prolong the smelting time and affect the uniformity of the alloy composition.

[0143] A comprehensive analysis of Examples 1 and 6-7 shows that if the alloying temperature is too high, manganese will volatilize and oxidize, resulting in inclusions and grain coarsening. If the temperature is too low, the alloying will be incomplete, manganese will not diffuse sufficiently, and the composition will be uneven and segregated, thus affecting the density and mechanical properties of the ingot.

[0144] (3) A comprehensive analysis of Examples 1 and 8-9 shows that the process parameters in the vacuum purification and refining process will affect the purity of the alloy.

[0145] (4) Comprehensive analysis of Examples 1 and 10-11 shows that a low cooling rate during solidification treatment in the casting process will reduce density and may cause a decrease in purity, while a high cooling rate will easily produce cracks and affect density.

[0146] (5) Comprehensive analysis of Example 1 and Comparative Example 1 shows that, compared with Example 1, the mixing method provided by Comparative Example 1 makes manganese more prone to rapid oxidation or volatilization at high temperature, which will lead to a decrease in alloy purity; at the same time, the melt is not mixed evenly and has poor fluidity, which makes it easy to produce shrinkage cavities and porosity after casting, thus reducing the density of the ingot.

[0147] (6) Comprehensive analysis of Example 1 and Comparative Example 2 shows that if the pre-melting and degassing process is omitted, the gas in the melt cannot escape fully, and porosity and inclusions are easily generated after casting, which will lead to a decrease in the density of the ingot. At the same time, it may cause local component segregation, affecting the purity and overall mechanical properties.

[0148] In summary, this invention effectively improves the purity, compositional uniformity, and microstructure density of copper-manganese alloys through a multi-stage vacuum smelting process controlled by pre-degassing, slow alloying, vacuum purification, and rate-controlled solidification, enabling batch, stable, and reproducible industrial production.

[0149] The applicant declares that the specific embodiments described above further illustrate the purpose, technical solution and beneficial effects of the present invention. It should be understood that the above description is only a specific embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A method for producing a high-purity copper-manganese alloy ingot, characterized by comprising: The preparation method comprises the following steps: ​ (1) pretreating raw copper and raw manganese to obtain treated copper particles and manganese particles; (2) melting the copper particles obtained in step (1) to obtain liquid copper, then mixing the manganese particles with the liquid copper to perform pre-melting and degassing to obtain a first alloy liquid; (3) adding manganese particles into the first alloy liquid obtained in step (2) at a controlled speed to perform alloying treatment, and then performing vacuum purification refining to obtain a second alloy liquid; (4) performing casting treatment on the second alloy liquid obtained in step (3) to obtain the high-purity copper-manganese alloy ingot.

2. The production method according to claim 1, characterized by, The purity of the raw copper in step (1) is ≥99.9999%. Preferably, the purity of the raw manganese in step (1) is ≥99.999%. Preferably, the pretreatment in step (1) comprises drying treatment. Preferably, the temperature of the drying treatment is 70-90°C. Preferably, the time of the drying treatment is 12-20h.

3. The production method according to claim 1 or 2, characterized by, The temperature of the melting treatment in step (2) is 1050-1100°C. Preferably, the mass ratio of the copper particles to the manganese particles in step (2) is 19:0.8-1.

2.

4. The production method according to any one of claims 1 to 3, characterized by, The temperature of the pre-melting and degassing in step (2) is 1020-1070°C. Preferably, the vacuum degree of the pre-melting and gas removal in step (2) is 5x10 -3 ~1x10 -4 Mbar. Preferably, the time of the pre-melting and degassing in step (2) is 1-2h.

5. The method of any one of claims 1-4, wherein, The adding speed of the manganese particles in step (3) is 0.6-1.0kg / min. Preferably, the adding amount of the manganese particles in step (3) is 5-5.5% of the mass of the first alloy liquid. The temperature of the alloying treatment in step (3) is 1130-1170°C.

6. The method of any one of claims 1-5, wherein, The temperature of the vacuum purification refining in step (3) is 1200-1300°C. Preferably, the vacuum degree of the vacuum purification refining of step (3) is 1 x 10 -5 ~ 1 x 10 -6 Mbar; Preferably, the time of the vacuum purification refining in step (3) is 2.5-3.5h.

7. The method of any one of claims 1-6, wherein, The casting treatment in step (4) comprises: pouring the second alloy liquid into a water-cooled mold to perform solidification treatment, and then performing air cooling treatment.

8. The preparation method according to claim 7, characterized in that, The vacuum degree of the casting process is 10 -2 ~ 10 - 3 Mbar; Preferably, the temperature of the second alloy liquid is 1180-1230°C. Preferably, the pouring speed is 0.6-0.8kg / s. Preferably, the cooling rate of the solidification treatment is 100-1000K / s. Preferably, the end temperature of the solidification treatment is 600-700°C. Preferably, the cooling rate of the air cooling treatment is 1-10K / s.

9. The method of any one of claims 1-8, wherein, The preparation method comprises the following steps: (1) drying raw copper and raw manganese at 70-90°C for 12-20h to obtain treated copper particles and manganese particles; (2) melting the copper particles obtained in step (1) to obtain liquid copper, then mixing the manganese particles with the liquid copper to perform pre-melting and degassing to obtain a first alloy liquid; Preferably, the mass ratio of the copper particles to the manganese particles is 19:0.8-1.2; The temperature of the pre-melting and degassing is 1020-1070℃, the vacuum degree is 5x10 -3 -1x10 -4 Mbar, and the time is 1-2h. (3) adding manganese particles into the first alloy liquid obtained in step (2) at a controlled speed to perform alloying treatment, and then performing vacuum purification refining to obtain a second alloy liquid; Preferably, the adding speed of the manganese particles is 0.6-1.0kg / min, and the temperature of the alloying treatment is 1130-1170°C; The temperature of the vacuum purification refining is 1200-1300 °C, the vacuum degree is 1 x 10 -5 ~ 1 x 10 -6 Mbar, and the time is 2.5-3.5 h. (4) at 10 -2 ~ 10 -3 A second alloy liquid at a temperature of 1180-1230°C is poured into a water-cooled mold to perform a solidification treatment under a vacuum degree of 10~10~4Mbar, and a high-purity copper-manganese alloy ingot is obtained after air cooling treatment. Preferably, the pouring speed is 0.6-0.8kg / s. The cooling rate of the solidification treatment is 100-1000 K / s, and the end temperature is 600-700 DEG C; the cooling rate of the air cooling treatment is 1-10 K / s.

10. A high-purity copper-manganese alloy ingot prepared by the method of any one of claims 1 to 9, characterized in that, The content of manganese in the high-purity copper-manganese alloy ingot is 4.5-5.5 wt%.

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