High-toughness high-thermal-conductivity medium-entropy alloy and preparation and application thereof

Abstract

The present application relates to the technical field of manufacturing and application of metal materials, and particularly relates to a high-strength high-toughness high-thermal-conductivity medium-entropy alloy and preparation and application thereof. The high-strength high-toughness high-thermal-conductivity alloy is prepared by vacuum induction melting or additive manufacturing, so that the base body generates multiple reinforcement phases such as Ni-rich phase, Cr-rich phase, Ni(AlTi) and Ni3(AlTi) in a dispersed distribution, and the alloy is endowed with extremely high room-temperature strength and high-temperature strength. The high-strength high-toughness high-thermal-conductivity alloy is mainly used in the field of molds and can also be applied in the high-temperature field. Compared with the prior art, the high-strength high-toughness high-thermal-conductivity medium-entropy alloy prepared in the present application has better hardness and excellent comprehensive mechanical properties; the present application adopts a melting method for preparation, and the method of additive manufacturing can also be used for preparing complex components, the process is simple and efficient, has higher economic benefits, and is suitable for industrialized mass production.

Description

Technical Field

[0001] This invention relates to the field of manufacturing and application technology of metallic materials, and in particular to a high-strength, high-toughness, high-thermal-conductivity, medium-entropy alloy and its preparation and application. Background Technology

[0002] In recent years, medium / high entropy alloys have broken away from the traditional "single principal component composition" design concept, creating new alloys with "multiple principal component compositions." The four major effects of medium / high entropy alloys—high entropy effect, hysteresis diffusion effect, lattice distortion effect, and "cocktail effect"—endow them with excellent comprehensive mechanical properties. Medium entropy alloys are generally prepared using melting, powder metallurgy, and additive manufacturing methods. Melting is a simple process that can produce large-size castings, making it suitable for industrial production. Additive manufacturing can produce alloy components with complex shapes, resulting in small grain sizes and uniform microstructure, thus exhibiting superior comprehensive mechanical properties. This invention relates to a high-strength, high-toughness, and high-thermal-conductivity medium-entropy alloy with multiple strengthening effects, which can be prepared using vacuum melting and can also be manufactured using additive manufacturing for complex-shaped components. While medium-entropy alloys possess excellent comprehensive mechanical properties, they still fall short in complex service environments in their original or as-cast state, thus requiring a series of strengthening treatments. Among the many alloy strengthening methods, second-phase strengthening is one of the most effective. Adding elements such as C and B can form carbide precipitation reinforcement in the matrix, adding Y₂O₃ oxide can form oxide dispersion reinforcement, and adding Ti and V to CoFeNi can form L 12 Particle strengthening (CN114457270A) and adding Al to medium-entropy alloys to form a second-phase precipitation strengthening (CN114807719A), along with other published patents such as the CoFeNiVZr high-entropy alloy containing Zr and V (CN108950349 B), all utilize second-phase precipitation strengthening, solid solution strengthening, or grain boundary strengthening, achieving certain strengthening effects. However, the types of strengthening phases are limited, resulting in limited strengthening effects. Therefore, there is a need to find a novel medium-entropy alloy with multiple strengthening phases and diverse strengthening effects to cope with various complex and changing service environments, expanding the alloy's application scenarios. Summary of the Invention

[0003] To address the aforementioned problems, the present invention aims to provide a high-strength, high-toughness, high-thermal-conductivity, medium-entropy alloy, its preparation, and its applications. The objective of this invention is to prepare a high-strength, high-toughness, high-thermal-conductivity, medium-entropy alloy with multiple strengthening effects through vacuum induction melting or additive manufacturing. This invention involves the additional addition of Cr, Ti, and Al elements during the melting or additive manufacturing process, and the improvement and control of the microstructure through heat treatment. This results in the formation of multiple strengthening phases in the matrix, including spherical Cr-rich phases, lamellar Ni-rich phases, and spherical or rod-shaped Ni(AlTi) and Ni3(AlTi) phases. The spherical Cr-rich phase, lamellar Ni-rich phase, and spherical or rod-shaped Ni(AlTi) phase play a major strengthening role in the low-temperature region (<500℃), while the spherical Ni3(AlTi) and spherical or rod-shaped Ni(AlTi) phases dominate the strengthening at high temperatures (>700℃). These multiple strengthening phases can each dominate their strengthening effect at different service temperatures and service times, achieving multi-phase coordinated strengthening and endowing the alloy with excellent comprehensive mechanical properties, enabling its application in various scenarios such as high-end molds and high-temperature service environments. The alloy is prepared by vacuum induction melting or additive manufacturing. The process is simple, compatible with the factory's existing production lines, suitable for industrial production, and has high economic benefits and application value.

[0004] The objective of this invention can be achieved through the following technical solutions:

[0005] The first objective of this invention is to provide a high-strength, high-toughness, high-thermal-conductivity, medium-entropy alloy comprising the following components by mass percentage:

[0006] Co: 30% to 45%, Fe: 30% to 40%, Ni: 12% to 18%, Al: 0% to 5%, Ti: 0% to 5%, Cr: 1% to 5%;

[0007] The sum of the mass percentages of the above components is 100%;

[0008] The high-strength, high-toughness, and high-thermal-conductivity medium-entropy alloy has a hardness of 457.6 HV to 661.1 HV and a thermal conductivity of 65 W / m·K to 78 W / m·K.

[0009] The second objective of this invention is to provide a method for preparing a high-strength, high-toughness, high-thermal-conductivity, medium-entropy alloy, which is prepared by a melting method or an additive manufacturing method.

[0010] In one embodiment of the present invention, the smelting method includes the following steps:

[0011] (A1) The ingots are obtained by smelting and post-processing each chemical element;

[0012] (A2) Heat-treat the ingot obtained in step (A1) to obtain a high-strength, high-toughness, high-thermal-conductivity, medium-entropy alloy.

[0013] In one embodiment of the present invention, in step (A1), the melting process is repeated 4 to 7 times to ensure the uniformity of the alloy composition;

[0014] The smelting process is carried out under vacuum, with a vacuum level of less than 10 Pa.

[0015] During the smelting process, once all the raw materials have melted, the vacuuming process is stopped, argon gas is added, and the smelting process is maintained.

[0016] The post-processing involves pouring the mixture into a mold, allowing it to stand at room temperature, and then removing it.

[0017] In one embodiment of the present invention, argon gas is replenished to 6 kPa;

[0018] In the smelting state, the temperature is 1550℃~1600℃ and the time is 10min~15min; the power frequency stirring is turned on to improve the uniformity of the molten steel.

[0019] In one embodiment of the present invention, the power supply for the heating and melting process is 500 kW, and the power supply for maintaining the molten steel temperature at around 1550°C to 1600°C is 450 kW.

[0020] In one embodiment of the present invention, in step (A2), the heat treatment is a solution treatment followed by aging treatment or annealing treatment;

[0021] Solution treatment involves first treating the ingot at 1100℃ for 0.5h, and then quenching it to room temperature at a cooling rate greater than 5℃ / s.

[0022] Aging or annealing involves holding the ingot at 400℃~800℃ for 2h~256h, and finally air-cooling it to room temperature.

[0023] In one embodiment of the present invention, the additive manufacturing method includes the following steps:

[0024] (B1) After mixing the powders of each chemical element, the pre-treated alloy is obtained by printing and molding according to a predetermined shape using additive manufacturing methods such as powder spreading or powder feeding.

[0025] (B2) The pretreated alloy obtained in step (B1) is heat-treated to obtain a high-strength, high-toughness, high-thermal-conductivity, medium-entropy alloy.

[0026] In one embodiment of the present invention, in step (B1), the printing process is carried out under an argon atmosphere;

[0027] During the printing process, the parameters are as follows: laser power between 60W and 1000W, scanning speed between 0.3m / s and 1.6m / s, powder layer thickness between 20μm and 185μm, scanning spacing between 2mm and 4mm, and interlayer cooling time between 50s and 150s.

[0028] In one embodiment of the present invention, the powder diameter in step (B1) is 10 μm to 90 μm, and can be ordered directly from the factory or enterprise.

[0029] In one embodiment of the present invention, in step (B2), during the heat treatment process, the sample is tempered at 400°C to 800°C for 2 hours to 256 hours.

[0030] In one embodiment of the present invention, a solution treatment can be performed before tempering, that is, heating to 1000℃~1200℃ for solution treatment for 1h~4h, and then quenching to room temperature with a cooling rate greater than 5℃ / s.

[0031] The heat-treated samples exhibit a variety of precipitated phase morphologies: spherical Cr-rich phases, lamellar Ni-rich phases, and spherical or rod-shaped Ni(AlTi) and Ni3(AlTi) phases, among other strengthening phases. These multiple strengthening phases can dominate the strengthening effect at different service temperatures and times, achieving multi-phase synergistic strengthening and endowing the alloy with excellent comprehensive mechanical properties. This enables the alloy to be used in various scenarios, including high-end molds and high-temperature service environments.

[0032] The third objective of this invention is to provide an application of a high-strength, high-toughness, high-thermal-conductivity, medium-entropy alloy in the field of high-end molds or in complex service rings suitable for high-temperature environments.

[0033] Compared with the prior art, the present invention has the following beneficial effects:

[0034] (1) This invention provides two methods for preparing high-strength, high-toughness, high-thermal-conductivity, medium-entropy alloys: smelting and additive manufacturing. The appropriate preparation method can be selected according to the specific circumstances, which is flexible and has a certain degree of selectivity.

[0035] (2) The high-strength, high-toughness, high-thermal-conductivity, medium-entropy alloy prepared by the present invention produces a variety of strengthening phases in the matrix after heat treatment, such as spherical Cr-rich phase, lamellar Ni-rich phase, spherical or rod-shaped Ni (AlTi) and Ni3 (AlTi) phase. These phases can exert their dominant strengthening effects at different service temperatures and service times, thereby achieving multi-phase coordinated strengthening and endowing the alloy with excellent comprehensive mechanical properties, meeting the requirements of high-end molds, and can also be used in complex service environments such as high temperature. Attached Figure Description

[0036] Figure 1SEM images of the as-cast microstructure, the microstructure after solution treatment, and the microstructure after aging or annealing at 400℃ for 32 hours in Example 1 of CoFe35Ni12Al5Ti5Cr2.

[0037] Figure 2 The image shows the SEM image of the microstructure of CoFe35Ni12Cr5Al5Ti2 after aging or annealing at 775℃ for 2 hours in Example 2. Figure 2 The image on the right is an enlarged view of the white box in the image on the left;

[0038] Figure 3 This is a SEM image of the tempered microstructure of CoFe40Ni15Cr1 after aging or annealing at 400℃ for 32 hours in Example 3. Detailed Implementation

[0039] This invention provides a high-strength, high-toughness, high-thermal-conductivity, medium-entropy alloy, comprising the following components by mass percentage:

[0040] Co: 30% to 45%, Fe: 30% to 40%, Ni: 12% to 18%, Al: 0% to 5%, Ti: 0% to 5%, Cr: 1% to 5%;

[0041] The sum of the mass percentages of the above components is 100%;

[0042] The high-strength, high-toughness, high-thermal-conductivity, medium-entropy alloy has a hardness of 457.6 HV to 661.1 HV and a thermal conductivity of 65 W / m·K to 78 W / m·K.

[0043] This invention provides a method for preparing a high-strength, high-toughness, high-thermal-conductivity, medium-entropy alloy, which is prepared by a melting method or an additive manufacturing method.

[0044] In one embodiment of the present invention, the smelting method includes the following steps:

[0045] (A1) The ingots are obtained by smelting and post-processing each chemical element;

[0046] (A2) Heat-treat the ingot obtained in step (A1) to obtain a high-strength, high-toughness, high-thermal-conductivity, medium-entropy alloy.

[0047] In one embodiment of the present invention, in step (A1), the melting process is repeated 4 to 7 times to ensure the uniformity of the alloy composition;

[0048] The smelting process is carried out under vacuum, with a vacuum level of less than 10 Pa.

[0049] During the smelting process, once all the raw materials have melted, the vacuuming process is stopped, argon gas is added, and the smelting process is maintained.

[0050] The post-processing involves pouring the mixture into a mold, allowing it to stand at room temperature, and then removing it.

[0051] In one embodiment of the present invention, argon gas is replenished to 6 kPa;

[0052] In the smelting state, the temperature is 1550℃~1600℃ and the time is 10min~15min; the power frequency stirring is turned on to improve the uniformity of the molten steel.

[0053] In one embodiment of the present invention, the power supply for the heating and melting process is 500 kW, and the power supply for maintaining the molten steel temperature at around 1550°C to 1600°C is 450 kW.

[0054] In one embodiment of the present invention, in step (A2), the heat treatment is a solution treatment followed by aging treatment or annealing treatment;

[0055] Solution treatment involves first treating the ingot at 1100℃ for 0.5h, and then quenching it to room temperature at a cooling rate greater than 5℃ / s.

[0056] Aging or annealing involves holding the ingot at 400℃~800℃ for 2h~256h, and finally air-cooling it to room temperature.

[0057] In one embodiment of the present invention, the additive manufacturing method includes the following steps:

[0058] (B1) After mixing the powders of each chemical element, the pre-treated alloy is obtained by printing and molding according to a predetermined shape using additive manufacturing methods such as powder spreading or powder feeding.

[0059] (B2) The pretreated alloy obtained in step (B1) is heat-treated to obtain a high-strength, high-toughness, high-thermal-conductivity, medium-entropy alloy.

[0060] In one embodiment of the present invention, in step (B1), the printing process is carried out under an argon atmosphere;

[0061] During the printing process, the parameters are as follows: laser power between 60W and 1000W, scanning speed between 0.3m / s and 1.6m / s, powder layer thickness between 20μm and 185μm, scanning spacing between 2mm and 4mm, and interlayer cooling time between 50s and 150s.

[0062] In one embodiment of the present invention, the powder diameter in step (B1) is 10 μm to 90 μm, and can be ordered directly from the factory or enterprise.

[0063] In one embodiment of the present invention, in step (B2), during the heat treatment process, the sample is tempered at 400°C to 800°C for 2 hours to 256 hours.

[0064] In one embodiment of the present invention, a solution treatment can be performed before tempering, that is, heating to 1000℃~1200℃ for solution treatment for 1h~4h, and then quenching to room temperature with a cooling rate greater than 5℃ / s.

[0065] The heat-treated samples exhibit a variety of precipitated phase morphologies: spherical Cr-rich phases, lamellar Ni-rich phases, and spherical or rod-shaped Ni(AlTi) and Ni3(AlTi) phases, among other strengthening phases. These multiple strengthening phases can dominate the strengthening effect at different service temperatures and times, achieving multi-phase synergistic strengthening and endowing the alloy with excellent comprehensive mechanical properties. This enables the alloy to be used in various scenarios, including high-end molds and high-temperature service environments.

[0066] This invention provides an application of a high-strength, high-toughness, high-thermal-conductivity, medium-entropy alloy in high-end mold applications or in complex service environments suitable for high-temperature conditions.

[0067] The present invention will now be described in detail with reference to the accompanying drawings and specific embodiments.

[0068] Unless otherwise specified, all reagents used in the following embodiments are commercially available reagents; and all detection methods and techniques used are conventional detection methods and techniques in the art.

[0069] Example 1

[0070] This embodiment provides a high-strength, high-toughness, high-thermal-conductivity, medium-entropy alloy and its preparation method.

[0071] A high-strength, high-toughness, high-thermal-conductivity, medium-entropy alloy, with the composition CoFe35Ni12Al5Ti5Cr2, is prepared by vacuum induction melting. First, raw materials are weighed according to the following weight percentages (Fe 35wt%, Ni 12wt%, Al 5wt%, Ti 5wt%, Cr 2wt%, with the remainder being Co), with a purity better than 99.95%. Due to the significant difference in melting point between Al and other elemental metals, and considering losses during the melting process, an additional 1.0wt% is added (totaling 6wt%). The weighed raw materials are then uniformly mixed and placed in a vacuum arc furnace for melting. The specific melting steps are as follows:

[0072] S1: Add raw materials. Place the prepared raw materials into the crucible of the vacuum melting furnace, close the furnace chamber, and continue to evacuate to <10Pa.

[0073] S2: Start smelting, heat until all raw materials are melted, the power supply during heating is 500kw. After the raw materials have melted, stop evacuation, fill the furnace chamber with high-purity argon gas to 6KPa, maintain the molten steel temperature at 1550℃~1600℃, the power supply at this time is 450kw, maintain this temperature for 12min.

[0074] S3: Pour molten steel into a mold, let it stand until it reaches room temperature, and then remove it to obtain an ingot.

[0075] The smelting process is repeated five times to obtain ingots with uniform composition.

[0076] The smelted ingots were subjected to heat treatment. The heat treatment consisted of solution treatment followed by aging or annealing. During solution treatment, the smelted sample was first solution treated at 1100℃ for 0.5h, and then quenched to room temperature at a cooling rate greater than 5℃ / s. During aging or annealing, the sample after solution treatment was held at 400℃ for 32h, and finally air-cooled to room temperature to obtain the high-strength, high-toughness, high-thermal-conductivity, medium-entropy alloy CoFe35Ni12Al5Ti5Cr2.

[0077] The sample matrix structure after heat treatment is as follows: Figure 1 As shown, heat treatment improved the microstructure of the alloy, resulting in the precipitation of various phases with different morphologies in the matrix: spherical Cr-rich phases, lamellar Ni-rich phases, and various strengthening phases such as spherical and rod-shaped Ni(AlTi) and Ni3(AlTi) phases.

[0078] At this temperature, the spherical Cr-rich phase, the lamellar Ni-rich phase, and the spherical and rod-shaped Ni (AlTi) phases play the main strengthening role. The final alloy after heat treatment has a hardness of 661.1 HV and a thermal conductivity of 68 W / m·K.

[0079] Example 2

[0080] This embodiment provides a high-strength, high-toughness, high-thermal-conductivity, medium-entropy alloy and its preparation method.

[0081] A high-strength, high-toughness, high-thermal-conductivity, medium-entropy alloy, with the composition CoFe35Ni12Cr5Al5Ti2, is prepared by vacuum induction melting. First, the raw materials are weighed according to the following weight percentages (Fe 35wt%, Ni 12wt%, Cr 5wt%, Al 5wt%, Ti 2wt%, with the remainder being Co), with a purity better than 99.95%. Due to the significant difference in melting point between Al and other elemental metals, and considering losses during the melting process, an additional 1.0wt% is added (totaling 6wt%). After uniformly mixing the weighed raw materials, the mixture is placed in a vacuum arc furnace for melting. The specific melting steps are as follows:

[0082] S1: Add raw materials. Place the prepared raw materials into the crucible of the vacuum melting furnace, close the furnace chamber, and continue to evacuate to <10Pa.

[0083] S2: Start smelting, heat until all raw materials are melted, the power supply during heating is 500kw. After the raw materials have melted, stop vacuuming, fill the furnace chamber with high-purity argon gas to 6KPa, maintain the molten steel temperature in the range of 1550℃~1600℃, the power supply at this time is 450kw, maintain this temperature for 10min.

[0084] S3: Pour molten steel into the mold, let it stand until it reaches room temperature, and then remove it.

[0085] Repeat step S2 five times to obtain a uniformly composed ingot.

[0086] The smelted ingots are subjected to heat treatment. The heat treatment is solution treatment followed by aging or annealing. During solution treatment, the smelted sample is first solution treated at 1100℃ for 0.5h, and then quenched to room temperature at a cooling rate greater than 5℃ / s. During aging or annealing, the sample after solution treatment is held at 775℃ for 2h, and finally air-cooled to room temperature.

[0087] The sample matrix structure after heat treatment is as follows: Figure 2 As shown. Figure 2 The right image is an enlarged view of the white box in the left image. Heat treatment improved the microstructure of the alloy, and various morphologies of precipitates formed in the matrix: spherical Cr-rich phases, lamellar Ni-rich phases, and various strengthening phases such as spherical or rod-shaped Ni (AlTi) and Ni3 (AlTi) phases.

[0088] At this temperature, the Ni3(AlTi) phase and rod-shaped Ni(AlTi) play the main strengthening role. The final alloy after heat treatment has a hardness of 457.6 HV and a thermal conductivity of 65 W / m·K.

[0089] Example 3

[0090] This embodiment provides a high-strength, high-toughness, high-thermal-conductivity, medium-entropy alloy and its preparation method.

[0091] A high-strength, high-toughness, high-thermal-conductivity, medium-entropy alloy, with the composition CoFe40Ni15Cr1, is printed using additive manufacturing. The raw material is a ball-milled elemental metal powder (40 wt% Fe, 15 wt% Ni, 1 wt% Cr, and the remainder Co), with a particle size of 40 μm to 60 μm. The raw materials are weighed and uniformly mixed according to their weight percentages, and then printed as follows:

[0092] The prepared powder is placed into the processing chamber, and high-purity argon gas is introduced as a protective gas. A powder-spreading feeding method is used, and the powder is printed according to predetermined parameters. The specific parameters are: laser power of about 120W, scanning rate of 0.81m / s, powder layer thickness of 42μm, scanning spacing of about 3mm, and interlayer cooling time of about 60s.

[0093] The printed sample was then subjected to heat treatment. The heat treatment process was as follows: the printed alloy sample was aged at 400℃ for 32 hours.

[0094] The microstructure after heat treatment is as follows Figure 3 As shown, the sample microstructure after heat treatment exhibits various morphologies of precipitated phases: spherical Cr-rich phases, lamellar Ni-rich phases, and other reinforcing phases. At this temperature, the spherical Cr-rich phases and lamellar Ni-rich phases play the main reinforcing roles.

[0095] The final alloy after heat treatment has a hardness of 658.5 HV and a thermal conductivity of 78 W / m·K.

[0096] The above description of the embodiments is provided to enable those skilled in the art to understand and use the invention. It will be apparent to those skilled in the art that various modifications can be made to these embodiments, and the general principles described herein can be applied to other embodiments without inventive effort. Therefore, the present invention is not limited to the above embodiments, and any improvements and modifications made by those skilled in the art based on the interpretation of the present invention, without departing from the scope of the invention, should be within the protection scope of the present invention.

Claims

1. A high-strength, high-toughness, high-thermal-conductivity, medium-entropy alloy, characterized in that, The components include the following percentages by mass: Fe: 35%, Ni: 12%, Al: 5%, Ti: 5%, Cr: 2%; balance Co; The high-strength, high-toughness, high-thermal-conductivity, medium-entropy alloy contains spherical Cr-rich phases, lamellar Ni-rich phases, and spherical or rod-shaped Ni (AlTi) and Ni3 (AlTi) phases; the high-strength, high-toughness, high-thermal-conductivity, medium-entropy alloy has a hardness of 661.1 HV and a thermal conductivity of 68 W / m•K. The high-strength, high-toughness, high-thermal-conductivity, medium-entropy alloy was prepared by a melting method. The smelting method includes the following steps: (A1) The ingots are obtained by post-processing after the melting of each chemical element; (A2) The ingot obtained in step (A1) is heat-treated to obtain a high-strength, high-toughness, high-thermal-conductivity, medium-entropy alloy; In step (A1), the smelting process is repeated 4 to 7 times; The smelting process is carried out under vacuum, with a vacuum level below 10 Pa. During the smelting process, once all the raw materials have melted, the vacuuming process is stopped, argon gas is added, and the smelting process is maintained. The post-processing involves pouring the mixture into a mold, allowing it to stand at room temperature, and then removing it. Replenish argon gas to 6 kPa; In the smelting state, the temperature is 1550 ℃~1600 ℃, and the time is 10 min~15 min; In step (A2), the heat treatment is a solution treatment followed by aging treatment or annealing treatment; Solution treatment involves first treating the ingot at 1100 ℃ for 0.5 h, and then quenching it to room temperature at a cooling rate greater than 5 ℃ / s. Aging or annealing involves holding the ingot at 400 ℃~800 ℃ for 2 h~256 h, and finally air cooling to room temperature.

2. A high-strength, high-toughness, high-thermal-conductivity, medium-entropy alloy, characterized in that, The components include the following percentages by mass: Fe: 40%, Ni: 15%, Cr: 1%; balance Co; The high-strength, high-toughness, high-thermal-conductivity, medium-entropy alloy contains spherical Cr-rich phases, lamellar Ni-rich phases, and spherical or rod-shaped Ni (AlTi) and Ni3 (AlTi) phases; the high-strength, high-toughness, high-thermal-conductivity, medium-entropy alloy has a hardness of 658.5 HV and a thermal conductivity of 78 W / m•K. The high-strength, high-toughness, high-thermal-conductivity, medium-entropy alloy was prepared by additive manufacturing. The additive manufacturing method includes the following steps: (B1) After mixing the powders of each chemical element, the pre-treated alloy is obtained by printing and molding according to a predetermined shape using additive manufacturing methods such as powder spreading or powder feeding. (B2) The pretreated alloy obtained in step (B1) is heat-treated to obtain a high-strength, high-toughness, high-thermal-conductivity, medium-entropy alloy. In step (B1), the printing process is carried out under an argon atmosphere; During the printing process, the parameters are as follows: laser power between 60 W and 1000 W, scanning speed between 0.3 m / s and 1.6 m / s, powder layer thickness between 20 μm and 185 μm, scanning spacing between 2 mm and 4 mm, and interlayer cooling time between 50 s and 150 s. In step (B2), during the heat treatment process, the sample is tempered at 400 ℃ to 800 ℃ for 2 h to 256 h.

3. The application of a high-strength, high-toughness, high-thermal-conductivity, medium-entropy alloy as described in any one of claims 1 to 2 in the field of high-end molds or in complex service environments at high temperatures.

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