Brass and preparation method thereof

Abstract

The invention relates to the technical field of metallurgy, and provides brass and a preparation method thereof.The preparation raw materials of the brass comprise the following components of 0.05-0.15 wt% of Al, 0.05-0.15 wt% of Cu, 0.05-0.15 wt% of Ti, 0.05- Si, 0.05 wt% to 0.15 wt%; 0.05 to 0.12 wt% of Fe; sn, 0.03 wt% to 0.20 wt%; 0.40 to 2 wt% of Bi; 0.40 to 2 weight percent of In; 32 to 45 wt% of Zn; and the balance of Cu. The brass prepared through the composition proportion of all the preparation raw materials has a stable alpha phase, a stable beta phase and a stable In-rich phase, the alpha phase is a matrix phase, the beta phase is distributed in the alpha phase, the In-rich phase is distributed in the alpha phase and at the grain boundary, the cutting performance of the brass can be improved while the strength, wear resistance and corrosion resistance of the brass are guaranteed, and the service life of the brass is prolonged. And a brass product prepared from the brass prepared from the elements greatly reduces pollution and harm to the environment and human bodies.

Description

Technical Field

[0001] The present application belongs to the field of metallurgy technology, and in particular relates to brass and a preparation method thereof. Background Art

[0002] Due to its excellent mechanical properties, corrosion resistance, casting properties, and formability, brass is widely used in a variety of industries, including bathroom fixtures, electrical equipment, and equipment manufacturing. Therefore, the machinability of brass is particularly important, as this property directly affects the production efficiency, product quality, and manufacturing costs of brass products in various fields.

[0003] In the related art, about 3% of Pb is usually added to brass to improve its cutting performance. Pb exists as an independent phase in Cu-Zn alloy. Since Pb is soft, brittle and has a low melting point, it can play a role in chip breaking, lubrication and cooling, thereby improving the cutting performance of brass. However, Pb is a toxic element and will cause environmental pollution during its production, processing and use. In particular, when lead brass is used in products that come into contact with water environments, Pb will precipitate in the form of ions and dissolve in water. Pb poisoning can damage the human blood, nerves, digestive and reproductive systems, and greatly endanger human health. In view of this, the development of a lead-free and environmentally friendly brass that is easy to cut and non-toxic and harmless to the human body and the environment has become an important issue that needs to be solved urgently. Summary of the Invention

[0004] The purpose of this application is to provide a brass and a preparation method thereof, which can improve the cutting performance of brass and solve the problem of harm to human body and environment.

[0005] To achieve the above application objectives, the technical solutions adopted in this application are as follows: In a first aspect, the present application provides a brass, wherein the raw materials for preparing the brass include the following components: Al, 0.05~0.15wt%; Si, 0.05~0.15wt%; Fe, 0.05~0.12wt%; Sn, 0.03~0.2wt%; Bi, 0.40~2wt%; In, 0.40~2wt%; Zn, 32~45wt%; The rest is Cu.

[0006] In the brass provided by the present application, 0.05-0.15wt% Al can form a γ phase in the copper matrix, thereby improving the strength and hardness of the alloy. In addition, since the aluminum oxide film formed by Al is dense and strong, it can improve the oxidation resistance of the alloy; 0.05-0.15wt% Si increases the volume fraction of the β phase and reduces the volume fraction of the α phase in the brass, which has the effect of improving the strength of the matrix; 0.05-0.12wt% Fe forms a fine and dispersed hard phase with Si, which plays a chip-breaking role during the cutting process, thereby improving the cutting performance of the brass; Bi is brittle and has a low melting point. It does not form a compound with Cu, but forms brittle, soft and dispersed small particles in the brass. The presence of Bi can create a tiny space in the alloy matrix, thereby cutting off the continuity of the matrix, becoming a stress concentration source, generating the so-called "notch effect", and forming many weakened micro-areas. During cutting, there are a large number of brittle but not hard bismuth particles on the contact surface of the blade, which is equivalent to reducing the cutting layer area, making the blade Tool wear is reduced, cutting temperature and cutting force are lowered, and surface roughness is also reduced, achieving the purpose of easy cutting; at the same time, 0.03~0.2wt% Sn interacts with 0.40~2wt% Bi to increase the surface tension of Bi, change the morphology and distribution of Bi element in the copper matrix, reduce the hot brittleness tendency of traditional easy-to-cut bismuth brass, and reduce the risk of brass cracking during hot working; 0.40~2wt% In can act as a lubricant during the cutting process, which is beneficial to improving the surface quality of the workpiece after cutting; 32~45wt% Zn can effectively adjust the phase structure of brass. The brass prepared with the above elements has stable α phase, β phase and In-rich phase, with α phase as the matrix phase, β phase distributed in α phase, and In-rich phase distributed in α phase and at grain boundaries. While ensuring the strength, wear resistance and corrosion resistance of brass, it can improve its cutting performance. In addition, brass products made of brass prepared with these elements greatly reduce pollution and harm to the environment and human body.

[0007] In some embodiments, the raw materials for preparing brass include the following components: Al, 0.05~0.12wt%; Si, 0.05~0.12wt%; Fe, 0.05~0.10wt%; Sn, 0.03~0.15wt%; Bi, 0.50~2wt%; In, 0.50~2wt%; Zn, 35~45wt%; The rest is Cu.

[0008] In a second aspect, the present application provides a method for preparing brass, the method comprising: Providing the components of the brass according to any one of the first aspects, and smelting the components to obtain a molten liquid; The molten liquid is drawn upward and continuously cast to obtain a brass ingot; The brass ingot is continuously extruded to obtain brass.

[0009] The brass production method provided in this application uses continuous casting to precisely control the shape and size of the brass ingot, resulting in a denser and more uniform internal structure. Continuous extrusion further improves the brass' microstructure and mechanical properties. This series of process steps enables the production of high-quality brass products with excellent machinability. This simple process also improves brass production efficiency.

[0010] In some embodiments, the step of smelting the components to obtain a molten solution comprises: Putting Cu into a melting device for smelting to obtain copper melt; Fe, Si, Al, Sn, Bi, In and Zn are sequentially added into the copper melt for smelting to obtain a melt.

[0011] In some embodiments, the step of placing Cu into a melting device for smelting to obtain a copper melt comprises: first placing Cu into a preheated melting device, then raising the melting temperature to 1250° C., and obtaining the copper melt after the Cu is melted.

[0012] In some embodiments, the sequential addition of Al, Si, Fe, Sn, Bi, In, and Zn to the copper melt for smelting to obtain a molten solution comprises: sequentially adding Fe, Si, and Al into the copper melt for smelting to obtain an alloy melt; Sn, Bi, In and Zn are added into the alloy melt at the same time for smelting to obtain a melt.

[0013] In some embodiments, the step of sequentially adding Fe, Si, and Al to the copper melt for smelting to obtain an alloy melt comprises: Adding Fe, Si and Al into copper melt in sequence for smelting to obtain semi-alloy melt; The semi-alloy melt is kept warm for 20-30 minutes and then cooled to 1090-1120° C. to obtain an alloy melt.

[0014] In some embodiments, the step of simultaneously adding Sn, Bi, In, and Zn to the alloy melt for smelting to obtain the melt comprises: Adding Sn, Bi, In and Zn simultaneously into the alloy melt for smelting to obtain an alloy liquid; The alloy liquid is kept warm for 10-15 minutes and then heated to 1150° C. to obtain a molten liquid.

[0015] In some embodiments, in the upward continuous casting of the molten liquid to obtain a brass ingot, the coolant temperature in the upward continuous casting is 20-25°C, the continuous casting speed is 80-150 mm / min, the stop time is 50-200 ms, the reverse thrust stroke is 0.1-0.3 mm, and a brass ingot with a diameter of 30 mm is obtained.

[0016] In some embodiments, in the continuous extrusion of the brass ingot, the extrusion temperature is 250-560° C., and the extrusion ratio is 1.3-1.9.

[0017] The above description is only an overview of the technical solution of the present application. In order to more clearly understand the technical means of the present application, it can be implemented in accordance with the contents of the specification. In order to make the above and other purposes, features and advantages of the present application more obvious and easy to understand, the specific implementation methods of the present application are listed below. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the following briefly introduces the drawings required for use in the embodiments or descriptions of the prior art. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0019] Figure 1 This is a schematic flow chart of the brass preparation method provided in the examples of the present application. DETAILED DESCRIPTION

[0020] In order to make the technical problems, technical solutions and beneficial effects to be solved by this application more clearly understood, the present application is further described in detail below in conjunction with the embodiments. It should be understood that the specific embodiments described herein are only used to explain this application and are not intended to limit this application.

[0021] In this application, the term "and / or" describes the relationship between associated objects, indicating that three possible relationships exist. For example, A and / or B can represent: A exists alone, A and B exist simultaneously, and B exists alone. A and B can be singular or plural. The character " / " generally indicates that the associated objects are in an "or" relationship.

[0022] In this application, "at least one" means one or more, and "plurality" means two or more. "At least one of the following" or similar expressions refers to any combination of these items, including any combination of single or plural items. For example, "at least one of a, b, or c" or "at least one of a, b and c" can all mean: a, b, c, ab (i.e., a and b), ac, bc, or abc, where a, b, and c can each be single or plural.

[0023] It should be understood that in the various embodiments of the present application, the size of the serial numbers of the above-mentioned processes does not mean the order of execution. Some or all of the steps can be executed in parallel or sequentially. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of the present application.

[0024] The terms used in the embodiments of the present application are for the purpose of describing specific embodiments only and are not intended to limit the present application. The singular forms "a", "an", "the" and "the" used in the embodiments of the present application and the appended claims are also intended to include plural forms unless the context clearly indicates otherwise.

[0025] The weights of the relevant components mentioned in the examples of this application may not only refer to the specific content of each component, but also represent the weight ratio between the components. Therefore, as long as the content of the relevant components is proportionally increased or decreased according to the examples of this application, it is within the scope disclosed in the examples of this application. Specifically, the masses described in the examples of this application may be mass units known in the chemical industry, such as μg, mg, g, and kg.

[0026] The terms "first" and "second" are used solely for descriptive purposes, to distinguish objects, such as substances, from one another. They should not be construed as indicating or implying relative importance or implicitly specifying the quantity of the technical features being referred to. For example, a first XX could also be referred to as a second XX, and similarly, a second XX could also be referred to as a first XX, without departing from the scope of the embodiments of this application. Thus, features defined as "first" or "second" may explicitly or implicitly include one or more of such features.

[0027] Brass refers to a class of alloys primarily composed of copper with specific alloying elements added to significantly enhance their elasticity and other mechanical properties. These alloys typically exhibit a high elastic limit, good fatigue resistance, and dimensional stability, making them valuable in applications requiring high precision and stability.

[0028] Due to its excellent mechanical properties, corrosion resistance, casting properties, and formability, brass is widely used in a variety of industries, including bathroom fixtures, electrical equipment, and equipment manufacturing. Therefore, the machinability of brass is particularly important, as this property directly affects the production efficiency, product quality, and manufacturing costs of brass products in various fields.

[0029] In related technologies, approximately 3% lead (Pb) is typically added to brass to improve its cutting performance. Pb exists as an independent phase in Cu-Zn alloys. Because Pb is soft, brittle, and has a low melting point, it can break chips, provide lubrication, and reduce temperatures, thereby improving the cutting performance of brass. However, Pb is a toxic element that can cause environmental pollution during its production, processing, and use. In particular, when lead brass is used in products that come into contact with water, Pb will precipitate and dissolve in water in the form of ions. Pb poisoning can damage the human blood, nervous system, digestive system, and reproductive system, posing a significant threat to human health.

[0030] Based on this, in order to improve the cutting performance of brass in the related art and solve the problem of harm to human body and environment, the embodiments of the present application provide the following solutions.

[0031] A first aspect of an embodiment of the present application provides brass, wherein raw materials for preparing the brass include the following components: Al 0.05-0.15 wt%; Si 0.05-0.15 wt%; Fe 0.05-0.12 wt%; Sn 0.03-0.20 wt%; Bi 0.40-2 wt%; In 0.40-2 wt%; Zn 32-45 wt%; and the remainder is Cu.

[0032] It can be understood that Al0.05~0.15wt% means that when the total weight of the raw materials is 100, Al is 0.05~0.15, for example, it can be 0.05, 0.10, 0.15, etc. Si0.05~0.15wt% means that when the total weight of the raw materials is 100, Si is 0.05~0.15, for example, it can be 0.05, 0.10, 0.15, etc. Fe0.05~0.12wt% means that when the total weight of the raw materials is 100, Fe is 0.05~0.12, for example, it can be 0.05, 0.10, 0.12, etc. Sn0.03~0.2wt% means that when the total weight of the raw materials is 100, Sn is 0.03~0.20, for example, it can be 0.03, 0.10, 0.15, 0.20, etc. Bi0.40-2wt% means that when the total weight of the raw materials is 100, Bi is 0.40-2, for example, 0.40, 1, 1.5, 2, etc. In0.40-2wt% means that when the total weight of the raw materials is 100, In is 0.40-2, for example, 0.40, 1, 1.5, 2, etc. Zn32-45wt% means that when the total weight of the raw materials is 100, Zn is 32-45, for example, 32, 40, 45, etc. The remainder is Cu means that after determining the component ratios of Zn, Al, Ni, and Ce, the remaining portion is entirely composed of Cu. For example, when the sum of the component ratios of Al, Si, Fe, Sn, Bi, In, and Zn is 45wt%, the component ratio of Cu is 55wt%, that is, when the total weight of the raw materials is 100 and the total weight of Al, Si, Fe, Sn, Bi, In, and Zn is 45, the weight of Cu is 55. When the total weight of the components of Al, Si, Fe, Sn, Bi, In and Zn is 35 wt%, the weight of Cu is 65 wt%, that is, when the total weight of the raw materials is 100 and the total weight of Al, Si, Fe, Sn, Bi, In and Zn is 35, the weight of Cu is 65, and so on.

[0033] From the above, it can be seen that in the brass provided in the embodiment of the present application, 0.05~0.15wt% Al can form a γ phase in the copper matrix, thereby improving the strength and hardness of the alloy. In addition, since the aluminum oxide film formed by Al is dense and strong, it can improve the oxidation resistance of the alloy; 0.05~0.15wt% Si increases the volume fraction of the β phase in the brass and reduces the volume fraction of the α phase, which has the effect of improving the strength of the matrix; 0.05~0.12wt% Fe forms a fine and dispersed hard phase with Si, which plays a chip-breaking role during the cutting process, thereby improving the cutting performance of the brass; Bi is brittle and has a low melting point. It does not form a compound with Cu, but forms brittle, soft and dispersed small particles in the brass. The presence of Bi can create a tiny space in the alloy matrix, thereby cutting off the continuity of the matrix, becoming a stress concentration source, generating the so-called "notch effect", and forming many weakened micro-areas. During cutting, there are a large number of brittle but not hard bismuth particles on the contact surface of the blade, which is equivalent to reducing the cutting layer area. , which reduces tool wear, lowers cutting temperature and cutting force, and reduces surface roughness, achieving the purpose of easy cutting; at the same time, 0.03~0.2wt% Sn interacts with 0.40~2wt% Bi to increase the surface tension of Bi, change the morphology and distribution of Bi element in the copper matrix, reduce the hot brittleness tendency of traditional easy-to-cut bismuth brass, and reduce the risk of brass cracking during hot working; 0.40~2wt% In can play a lubricating role in the cutting process, which is beneficial to improving the surface quality of the workpiece after cutting; 32~45wt% Zn can effectively adjust the phase structure of brass. The brass prepared by the above elements has stable α phase, β phase and In-rich phase, with α phase as the matrix phase, β phase distributed in α phase, and In-rich phase distributed in α phase and at grain boundaries. While ensuring the strength, wear resistance and corrosion resistance of brass, it can improve its cutting performance, and brass products made of brass prepared with these elements greatly reduce pollution and harm to the environment and human body.

[0034] In some embodiments, the raw materials for preparing brass include the following components: Al 0.05-0.12 wt%; Si 0.05-0.12 wt%; Fe 0.05-0.10 wt%; Sn 0.03-0.15 wt%; Bi 0.50-2 wt%; In 0.50-2 wt%; Zn 35-45 wt%; and the remainder is Cu.

[0035] This configuration further optimizes the content range of each element, within which the synergistic effects between them are even more pronounced. While ensuring improved alloy strength and cutting performance, it also reduces the potential brittleness risk associated with excessive levels of some elements. This helps further enhance brass's machinability, wear resistance, and phase structure stability, ultimately achieving a more optimal balance of strength, wear resistance, corrosion resistance, and cutting performance, meeting the needs of more specialized applications.

[0036] See also Figure 1 A second aspect of the embodiment of the present application provides a method for preparing brass, the method comprising: S100, providing the components of brass as described in any of the above embodiments, and smelting the components to obtain a molten liquid.

[0037] S200, the molten liquid is drawn upward and continuously cast to obtain a brass ingot.

[0038] S300, continuously extruding the brass ingot to obtain brass.

[0039] As can be seen from the above, the brass production method provided in the embodiments of this application, through upward continuous casting, can precisely control the shape and size of the brass ingot, making the internal structure more dense and uniform. Continuous extrusion further improves the brass microstructure and enhances its mechanical properties. Through this series of process steps, high-quality brass products with excellent cutting performance can be produced. The simple process steps can also improve brass production efficiency.

[0040] In some embodiments, in step S100, the components are smelted to obtain a molten liquid, including: S110, putting Cu into a melting device for smelting to obtain copper melt.

[0041] S120, sequentially adding Fe, Si, Al, Sn, Bi, In and Zn into the copper melt for smelting to obtain a molten solution.

[0042] It is understood that the smelting device can be a crucible furnace, an induction furnace, or other smelting equipment. The smelting is carried out in an atmospheric environment.

[0043] This setup allows copper to be smelted first to create a copper melt, providing a uniform base liquid environment for the subsequent addition of other elements. Sequentially adding other elements allows each element to be gradually and evenly incorporated into the copper melt, ensuring a uniform composition in the resulting melt and avoiding issues like element segregation, thereby ensuring consistent brass product quality.

[0044] In some embodiments, in step S110, Cu is placed in a melting device for smelting to obtain copper melt, including: first placing Cu in a preheated melting device, then raising the melting temperature to 1250°C, and obtaining copper melt after Cu is melted.

[0045] For example, when using a crucible furnace for smelting, the crucible can be preheated to dark red, then Cu is added, and then the temperature is quickly raised to 1250°C; when using an induction furnace for smelting, the furnace cavity of the induction furnace can be preheated to 200~300°C, Cu is placed in the induction furnace, and then the power parameters of the induction furnace are adjusted to raise the temperature to 1250°C at a faster rate.

[0046] This preheating and melting device reduces heating time, improves energy efficiency, and mitigates the rapid heat loss during the Cu melting process caused by low device temperatures, which can affect the melting effect. Raising the temperature to 1250°C completely melts the Cu without causing excessive oxidation or volatilization of other elements subsequently added.

[0047] In some embodiments, in step S120, Fe, Si, Al, Sn, Bi, In, and Zn are sequentially added to a copper melt for smelting to obtain a molten solution, including: S121, sequentially adding Fe, Si, and Al into the copper melt for smelting to obtain an alloy melt.

[0048] S122, Sn, Bi, In and Zn are added to the alloy melt at the same time for smelting to obtain a melt.

[0049] It can be understood that adding Fe, Si, and Al to the copper melt in sequence means adding Fe to the copper melt, then adding Si after a predetermined time, and then adding Al after a preset time, so that Fe, Si, and Al can be evenly dispersed in the copper melt.

[0050] With this setup, the interactions and diffusion mechanisms of Fe, Si, and Al with Cu differ. Adding them sequentially allows them to fully react with the molten copper and diffuse evenly, forming a stable alloy structure. Adding Sn, Bi, In, and Zn simultaneously reduces smelting time, and their interactions are more effective when added simultaneously, collectively impacting the alloy's properties, such as by changing the morphology and distribution of Bi. Adding different elements in stages for smelting fully accounts for their characteristics, allowing them to better function during the smelting process and further optimizing the alloy's composition and microstructure, thereby enhancing the overall performance of brass.

[0051] In some embodiments, in step S121, Fe, Si, and Al are sequentially added to a copper melt for smelting to obtain an alloy melt, including: S1211, Fe, Si, and Al are sequentially added to the copper melt for smelting to obtain a semi-alloy melt.

[0052] S1212, keeping the semi-alloy melt at a temperature of 20-30 minutes and then cooling it to 1090-1120°C to obtain an alloy melt.

[0053] It is understood that the holding time of 20-30 minutes may be 20 minutes, 25 minutes, 30 minutes, etc., but is not limited thereto. The cooling time of 1090-1120°C may be 1090°C, 1100°C, 1120°C, etc., but is not limited thereto.

[0054] This 20-30 minute holding period allows for full reaction between Fe, Si, and Al and the copper melt, facilitating full diffusion and uniform distribution of the elements, resulting in a stable semi-alloy melt structure. Cooling to 1090-1120°C prevents volatilization or overreaction of the elements due to excessive temperatures. Furthermore, this temperature range facilitates overall system stability and controllability when other elements are subsequently added. This holding and cooling process further optimizes the composition and structure of the semi-alloy melt, creating favorable conditions for the subsequent addition of elements such as Sn, Bi, In, and Zn, ultimately forming a high-performance brass melt and ensuring the stability and consistency of brass product quality.

[0055] In some embodiments, in step S122, Sn, Bi, In, and Zn are simultaneously added to a molten alloy for smelting to obtain a molten alloy, comprising: S1221, Sn, Bi, In and Zn are added to the alloy melt at the same time for smelting to obtain an alloy liquid.

[0056] S1222, keep the alloy liquid warm for 10 to 15 minutes and then raise the temperature to 1150°C to obtain a molten liquid.

[0057] It is understandable that the 10-15 min insulation period can be 10 min, 13 min, 15 min, etc., but is not limited thereto.

[0058] With this setup, a 10-15 minute hold allows Sn, Bi, In, and Zn to fully integrate into the molten alloy, allowing them to interact better with the previously formed alloy components and become evenly distributed throughout the system. Raising the temperature to 1150°C improves the fluidity of the molten alloy, further facilitating compositional uniformity. This temperature also ensures the stable presence of each element without significant volatilization, ensuring the quality of the final melt. This combination of holding and heating helps optimize the distribution and interaction of Sn, Bi, In, and Zn within the alloy, enhancing the overall performance of brass.

[0059] In some embodiments, in step S200, the molten liquid is upwardly drawn and continuously cast to obtain a brass ingot. The temperature of the coolant in the upward continuous casting is 20-25°C, the continuous casting speed is 80-150 mm / min, the stop time is 50-200 ms, and the reverse thrust stroke is 0.1-0.3 mm, thereby obtaining a brass ingot with a diameter of 30 mm.

[0060] It is understood that the crystallizer used for upward continuous casting with a 30mm sizing zone can be made of materials such as alumina, silicon carbide, graphite, or boron nitride. However, alumina has poor thermal conductivity, resulting in low production efficiency; silicon carbide has a high coefficient of thermal expansion and poor lubricity, resulting in low sample surface quality and dimensional accuracy; and graphite reacts with the iron in the alloy. Boron nitride crystallizers are more suitable. The coolant temperature is 20-25°C, for example, 20°C, 23°C, 25°C, etc., but not limited to these. The continuous casting speed is 80-150 mm / min, for example, 80 mm / min, 110 mm / min, 150 mm / min, etc., but not limited to these. The dwell time is 50-200 ms, for example, 50 ms, 150 ms, 200 ms, etc., but not limited to these. The backfeed stroke is 0.1-0.3 mm, for example, 0.1 mm, 0.2 mm, 0.3 mm, etc., but not limited to these.

[0061] With this setting, the coolant temperature is between 20 and 25°C, which can effectively remove the heat during the solidification process of the ingot, ensuring that the ingot solidifies quickly and evenly, and reducing internal defects caused by too fast or too slow cooling. The continuous casting speed of 80 to 150 mm / min, the stop time of 50 to 200 ms, and the reverse push stroke of 0.1 to 0.3 mm work together to control the solidification process and internal structure formation of the ingot. The continuous casting speed affects the crystallization rate and the density of the internal structure of the ingot; the stop time helps to improve the local solidification conditions of the ingot and refine the grains; the reverse push stroke can increase the density of the ingot. Precise control of the various parameters of the upward continuous casting can produce brass ingots with uniform and dense internal structure, good surface quality, and dimensions that meet the requirements, providing high-quality billets for the subsequent continuous extrusion process, thereby improving the quality of the final brass product.

[0062] In some embodiments, in step S300, the brass ingot is continuously extruded, the extrusion temperature of the continuous extrusion is 250-560°C, and the extrusion ratio is 1.3-1.9.

[0063] It is understood that the extrusion temperature is 250-560° C., for example, 250° C., 400° C., 560° C., etc., but not limited thereto. The extrusion ratio is 1.3-1.9, for example, 1.3, 1.5, 1.9, etc., but not limited thereto.

[0064] This setting, with an extrusion temperature between 250°C and 560°C, improves the plasticity of brass, allowing it to deform plastically without cracking or other defects during the extrusion process. By properly controlling the extrusion temperature and extrusion ratio, the brass microstructure can be further improved, such as by refining the grains and eliminating internal defects, thereby enhancing its overall mechanical properties, including strength, toughness, and wear resistance.

[0065] The following describes the details in conjunction with specific embodiments.

[0066] Example 1 1) Prepare 0.10 wt% Al, 0.10 wt% Si, 0.10 wt% Fe, 0.10 wt% Sn, 1.3 wt% Bi, 1.3 wt% In, 38 wt% Zn, and 59 wt% Cu according to the composition ratio. Melt in an induction melting furnace, charge a graphite clay crucible, and use charcoal, borax, and cullet as a covering agent, where the covering agent is composed of 63% charcoal and borax and 37% cullet. First, preheat the crucible to dark red, then add Cu, and quickly raise the temperature to 1250°C. After Cu melts, a copper melt is obtained. Then, Fe, Si, and Al are sequentially added to the copper melt for smelting to obtain a semi-alloy melt. After keeping the melt warm for 25 minutes, the power is turned off. When the temperature of the semi-alloy melt is 1100°C, Sn, Bi, In, and Zn are added simultaneously to obtain an alloy liquid. After keeping the alloy liquid warm for 12 minutes, the temperature is raised to 1150°C to obtain a molten liquid.

[0067] 2) The molten liquid is upwardly drawn and continuously cast, using boron nitride as the crystallizer material. The coolant temperature of the upward continuous caster is controlled to 22°C, the continuous casting speed is 120 mm / min, the stop time is 150 ms, and the reverse thrust stroke is 0.2 mm to obtain a brass ingot with a diameter of 30 mm.

[0068] 3) The brass ingot is extruded in an extruder at a temperature of 400° C. and an extrusion ratio of 1.6 to obtain brass.

[0069] Example 2 1) Prepare a composition consisting of 0.05 wt% Al, 0.15 wt% Si, 0.12 wt% Fe, 0.03 wt% Sn, 0.40 wt% Bi, 0.40 wt% In, 32 wt% Zn, and 66.85 wt% Cu (balance). Melt the mixture in an induction melting furnace, charge a graphite clay crucible, and use charcoal, borax, and cullet as a covering agent, where the covering agent consists of 63% charcoal and borax and 37% cullet. First, preheat the crucible to dark red, then add Cu, and quickly raise the temperature to 1250°C. After Cu melts, a copper melt is obtained. Fe, Si, and Al are sequentially added to the copper melt for smelting to obtain a semi-alloy melt. After keeping the melt warm for 20 minutes, the power is turned off. When the temperature of the semi-alloy melt is 1090°C, Sn, Bi, In, and Zn are added simultaneously to obtain an alloy liquid. The alloy liquid is kept warm for 10 minutes and then raised to 1150°C to obtain a molten liquid.

[0070] 2) The molten liquid is continuously cast upward, using boron nitride as the crystallizer material. The coolant temperature of the upward continuous caster is controlled to 20°C, the continuous casting speed is 80 mm / min, the stop time is 50 ms, and the reverse push stroke is 0.1 mm to obtain a brass ingot with a diameter of 30 mm.

[0071] 3) The brass ingot is extruded in an extruder at a temperature of 250° C. and an extrusion ratio of 1.3 to obtain brass.

[0072] Example 3 1) Prepare a composition consisting of 0.15 wt% Al, 0.05 wt% Si, 0.05 wt% Fe, 0.20 wt% Sn, 2 wt% Bi, 2 wt% In, 45 wt% Zn, and 50.55 wt% Cu (balance). Melt the mixture in an induction melting furnace, charge a graphite clay crucible, and use charcoal, borax, and cullet as a covering agent, where the covering agent consists of 63% charcoal and borax and 37% cullet. First, preheat the crucible to dark red, then add Cu, and quickly raise the temperature to 1250°C. After Cu melts, a copper melt is obtained. Fe, Si, and Al are sequentially added to the copper melt for smelting to obtain a semi-alloy melt. Keep warm for 30 minutes and then turn off the power. When the temperature of the semi-alloy melt is 1120°C, Sn, Bi, In, and Zn are added simultaneously to obtain an alloy liquid. Keep the alloy liquid warm for 15 minutes and then raise the temperature to 1150°C to obtain a molten liquid.

[0073] 2) The molten liquid is upwardly casted, using boron nitride as the crystallizer material. The coolant temperature of the upward continuous caster is controlled to 25°C, the continuous casting speed is 150 mm / min, the stop time is 200 ms, and the reverse push stroke is 0.3 mm to obtain a brass ingot with a diameter of 30 mm.

[0074] 3) The brass ingot is extruded in an extruder at a temperature of 560° C. and an extrusion ratio of 1.9 to obtain brass.

[0075] Comparative Example 1 1) Prepare a composition consisting of 0.15wt% Al, 0.15wt% Sn, 1.7wt% In, 40wt% Zn, and 58wt% Cu (balance). Melt the mixture in an induction melting furnace, charging a graphite clay crucible with charcoal, borax, and cullet as a covering agent (63% charcoal, borax, and 37% cullet). Preheat the crucible to a dark red color, then add Cu and rapidly heat to 1250°C. Once the Cu melts, a copper melt is obtained. Al is then added to the copper melt and smelted to obtain a semi-alloyed solution. This solution is held at this temperature for 25 minutes before power is turned off. When the semi-alloyed solution reaches 1100°C, Sn, In, and Zn are added simultaneously to obtain a molten alloy. The alloy is held at this temperature for 13 minutes before being heated to 1150°C to obtain a molten solution.

[0076] 2) The molten liquid is upwardly casted, using boron nitride as the crystallizer material. The coolant temperature of the upward continuous caster is controlled at 23°C, the continuous casting speed is 110 mm / min, the stop time is 150 ms, and the reverse thrust stroke is 0.2 mm to obtain a brass ingot with a diameter of 30 mm.

[0077] 3) The brass ingot is extruded in an extruder at a temperature of 400° C. and an extrusion ratio of 1.6 to obtain brass.

[0078] Comparative Example 2 1) Prepare 0.10wt% Al, 0.10wt% Si, 0.10wt% Fe, 0.10wt% Sn, 1.3wt% Bi, 1.3wt% In, 38wt% Zn, and 59wt% Cu according to the composition ratio. Melt the mixture in an induction melting furnace, using a graphite clay crucible as the charge. Use charcoal, borax, and cullet as the covering agent, with the covering agent consisting of 63% charcoal and borax and 37% cullet. Preheat the crucible to a dark red color, then add Cu and rapidly heat to 1250°C. Once the Cu melts, a copper melt is obtained. Simultaneously add Fe, Si, Al, Sn, Bi, In, and Zn to obtain a molten alloy. Hold the alloy for 12 minutes and then heat to 1150°C to obtain a molten solution.

[0079] 2) The molten liquid is upwardly drawn and continuously cast, using boron nitride as the crystallizer material. The coolant temperature of the upward continuous caster is controlled to 22°C, the continuous casting speed is 120 mm / min, the stop time is 150 ms, and the reverse thrust stroke is 0.2 mm to obtain a brass ingot with a diameter of 30 mm.

[0080] 3) The brass ingot is extruded in an extruder at a temperature of 400° C. and an extrusion ratio of 1.6 to obtain brass.

[0081] Comparative Example 3 1) Prepare 0.10wt% Al, 0.10wt% Si, 0.10wt% Fe, 0.10wt% Sn, 1.3wt% Bi, 1.3wt% In, 38wt% Zn, and 59wt% Cu according to the composition ratio. Melt the mixture in an induction melting furnace, using a graphite clay crucible as the filling material. Use charcoal, borax, and cullet as the covering agent, where the covering agent is composed of 63% charcoal and borax and 37% cullet. Preheat the crucible to a dark red color, then add Cu and rapidly heat to 1250°C. Once the Cu melts, a copper melt is obtained. Add Fe, Si, and Al to the copper melt in sequence and smelt to obtain a semi-alloyed melt. Sn, Bi, In, and Zn are then added simultaneously to obtain a molten solution.

[0082] 2) The molten liquid is upwardly casted, using boron nitride as the crystallizer material. The coolant temperature of the upward continuous caster is controlled to 25°C, the continuous casting speed is 150 mm / min, the stop time is 200 ms, and the reverse push stroke is 0.3 mm to obtain a brass ingot with a diameter of 30 mm.

[0083] 3) The brass ingot is extruded in an extruder at a temperature of 560° C. and an extrusion ratio of 1.9 to obtain brass.

[0084] The brasses prepared in all the above examples and comparative examples were tested for hardness, strength and cutting performance. The testing methods are as follows: 1. Hardness test method: The alloy samples were hardness tested using an MHV-1000BZ Vickers hardness tester with a load of 500 gf and a loading time of 10 seconds. Ten hardness measurements were performed on each sample, and the average value was taken. Before measurement, the samples were cut into 15 mm x 15 mm pieces and polished smooth on the top and bottom surfaces using 300, 600, 1000, and 2000 grit sandpaper.

[0085] 2. Strength test method: The hardness of the alloy samples was tested using a Sansi Zongheng UTM5305-G electronic universal testing machine at a test rate of 10 mm / min. Each alloy sample was tested 3 times, and the average value was taken.

[0086] 3. Cutting performance test method: The reference sample, HPb62-3, and the test sample were placed on the same automatic lathe equipped with a cutting force dynamometer and subjected to cutting force testing under identical test conditions (lathe spindle speed, cutting speed, alloy tool and its parameters, feed rate, cutting conditions, ambient temperature, etc.). For each sample, at least three sets of average data for the cutting force F (including the three components of axial force Fx, radial force Fy, and main cutting force Fz) were collected, with each set of test data collected from at least 50 points.

[0087] Determine the cutting parameters: (1) Fine turning: cutting amount is 0.5 mm, rotation speed is 820 r / min, and tool speed is 0.260 mm / r; (2) Rough turning: cutting amount is 1 mm, rotation speed is 610 r / min, and tool speed is 0.260 mm / r (select one of the cutting parameters, fine turning or rough turning).

[0088] The main cutting force Fz is used to represent the cutting force. Since the other two components of the cutting force, the axial force Fx and the radial force Fy, have little influence on cutting and can be ignored, the measured main cutting force Fz is used as an approximate cutting force value to evaluate cutting performance. The calculation formula for evaluating cutting performance is shown below: W=(Fz / Fa)×100%. In the formula: W - relative cutting rate, in percentage (%); Fa—The main cutting force of HPb62-3 alloy, in Newton (N); Fz is the main cutting force of the tested alloy, in Newton (N).

[0089] The test results are shown in Table 1 below.

[0090] Table 1 According to the test data in Table 1, the brass prepared using the brass preparation raw materials and preparation method of the present application has relatively excellent cutting performance and can maintain good hardness and strength.

[0091] The above description is only a preferred embodiment of the present application and is not intended to limit the present application. Any modifications, equivalent replacements and improvements made within the spirit and principles of the present application should be included in the scope of protection of the present application.

Claims

1. A brass, characterized in that: The raw materials for preparing the brass include the following components: Al, 0.05~0.15wt%; Si, 0.05~0.15wt%; Fe, 0.05~0.12wt%; Sn, 0.03~0.20wt%; Bi, 0.40~2wt%; In, 0.40~2wt%; Zn, 32~45wt%; The rest is Cu.

2. The brass according to claim 1, characterized in that The raw materials for preparing the brass include the following components: Al, 0.05~0.12wt%; Si, 0.05~0.12wt%; Fe, 0.05~0.10wt%; Sn, 0.03~0.15wt%; Bi, 0.50~2wt%; In, 0.50~2wt%; Zn, 35~45wt%; The rest is Cu.

3. A method for preparing brass, characterized in that: The brass preparation method comprises: Providing the brass components according to any one of claims 1 to 2, and smelting the components to obtain a molten liquid; The molten liquid is drawn upward and continuously cast to obtain a brass ingot; The brass ingot is continuously extruded to obtain brass.

4. The brass preparation method according to claim 3, characterized in that: The process of smelting the components to obtain a molten liquid comprises: Putting Cu into a melting device for smelting to obtain copper melt; Fe, Si, Al, Sn, Bi, In and Zn are sequentially added into the copper melt for smelting to obtain a melt.

5. The brass preparation method according to claim 4, characterized in that: The method of placing Cu into a melting device for smelting to obtain a copper melt comprises: first placing Cu into a preheated melting device, then raising the melting temperature to 1250° C., and obtaining the copper melt after the Cu is melted.

6. The brass preparation method according to claim 5, characterized in that: The step of sequentially adding Al, Si, Fe, Sn, Bi, In and Zn to the copper melt for smelting to obtain a molten solution comprises: sequentially adding Fe, Si, and Al into the copper melt for smelting to obtain an alloy melt; Sn, Bi, In and Zn are added into the alloy melt at the same time for smelting to obtain a melt.

7. The brass preparation method according to claim 6, characterized in that: The step of sequentially adding Fe, Si, and Al into the copper melt for smelting to obtain an alloy melt comprises: Adding Fe, Si and Al into copper melt in sequence for smelting to obtain semi-alloy melt; The semi-alloy melt is kept warm for 20-30 minutes and then cooled to 1090-1120° C. to obtain an alloy melt.

8. The brass preparation method according to claim 6, characterized in that: The step of simultaneously adding Sn, Bi, In and Zn into the alloy melt for smelting to obtain the melt comprises: Adding Sn, Bi, In and Zn simultaneously into the alloy melt for smelting to obtain an alloy liquid; The alloy liquid is kept warm for 10-15 minutes and then heated to 1150° C. to obtain a molten liquid.

9. The brass preparation method according to claim 3, characterized in that: In the process of upward continuous casting of the molten liquid to obtain a brass ingot, the coolant temperature in the upward continuous casting is 20-25° C., the continuous casting speed is 80-150 mm / min, the stop time is 50-200 ms, the reverse thrust stroke is 0.1-0.3 mm, and a brass ingot with a diameter of 30 mm is obtained.

10. The brass preparation method according to claim 8, characterized in that: In the continuous extrusion of the brass ingot, the extrusion temperature is 250-560° C., and the extrusion ratio is 1.3-1.9.

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