CrCuAg alloy target for antibacterial plating and method for manufacturing the same

Abstract

The application relates to the technical field of target materials, and provides a CrCuAg alloy target material for antibacterial plating and a preparation method thereof, wherein the preparation method comprises the following steps: mixing Cr powder, Cu powder and Ag powder under the protection of inert gas to obtain mixed powder through mechanical ball milling; filling the mixed powder into a can, and the relative density of the filled can is greater than or equal to 55 %; performing vacuum thermal degassing on the filled can; performing hot isostatic pressing liquid phase sintering on the can after the vacuum thermal degassing is completed to obtain a CrCuAg alloy target material blank; and removing the can from the CrCuAg alloy target material blank to obtain the CrCuAg alloy target material. Through the synergistic design of the specific particle size grading and the hot isostatic pressing liquid phase sintering process, the densification problem caused by the large melting point difference of Cr, Cu and Ag is solved, the high-performance antibacterial alloy target material with a relative density greater than 99 % can be prepared, and the Cr substrate has high hardness and wear resistance and the Cu and Ag have the synergistic antibacterial function.

Description

Technical Field

[0001] This invention relates to the field of target preparation technology, and in particular to a CrCuAg alloy target for antibacterial coating and its preparation method. Background Technology

[0002] Metallic chromium (Cr) possesses high hardness, high wear resistance, excellent acid and alkali corrosion resistance, and chemical stability. Its coatings and alloy films are widely used in decorative coatings, tool coatings, magnetic recording coatings, microelectronic coatings, and optical coatings. With increasing demands for public health and safety, endowing Cr coatings with antibacterial properties has become an important technological development direction. Silver (Ag) ions have strong and long-lasting antibacterial properties, and copper (Cu) also possesses antibacterial capabilities; their synergy can significantly enhance the antibacterial effect. Therefore, developing Cr-Cu-Ag ternary alloy targets that, while maintaining the high hardness, high wear resistance, and corrosion resistance of Cr coatings, also endows them with long-lasting antibacterial functions, has significant application value.

[0003] However, the preparation of Cr-Cu-Ag alloy targets faces significant technical challenges. The melting points of the three elements Cr, Cu, and Ag differ greatly (Cr is about 1907℃, Cu is about 1085℃, and Ag is about 962℃), and the miscibility of Cr with Cu and Ag is limited. It is difficult to obtain high-density, uniformly composed alloy targets using conventional processes.

[0004] The smelting process involves melting and casting raw materials to form a shape. Although it can reduce the oxygen content, it has the following defects: (1) For multi-component systems with large differences in melting point, it is easy to produce component segregation and inclusion porosity; (2) The relative density of Cr alloy target material is difficult to reach more than 99%; (3) The casting structure has large grains, which affects the quality of sputtered film.

[0005] Powder metallurgy is the main method for preparing Cr alloy sputtering targets, and it mainly includes: (1) Vacuum hot pressing sintering process: The powder is loaded into a graphite mold and sintered under uniaxial pressure in a vacuum hot pressing furnace. This process only applies longitudinal pressure and cannot achieve isotropic pressure, so the target material is prone to internal defects and low relative density. If the relative density of Cr alloy target material is increased to more than 99%, the sintering temperature and pressure need to be increased, but brittle mesophase is easily generated, which deteriorates the processing performance and film quality.

[0006] (2) Hot isostatic pressing (HIP) sintering process: The powder is packed into a sleeve, vacuumed, and then placed in a sealed container for high-temperature and high-pressure sintering. This process can achieve isotropic pressing, and the densification effect is better than that of vacuum hot pressing. However, for the Cr-Cu-Ag system, if the sintering temperature is not properly controlled, it is still difficult to solve the problems of component segregation and insufficient density.

[0007] In traditional methods, such as the invention patent CN111719127A which discloses a vacuum melting preparation method for nickel-chromium-aluminum-yttrium-silicon alloy targets, intermediate alloys are prepared through multi-step melting. This process is cumbersome, and for the Cr-Cu-Ag system with greater melting point differences, Cu and Ag are easily lost through volatilization during the melting process, and compositional segregation is very likely to occur.

[0008] Invention patent CN102021460B discloses a method for preparing W-10Ti alloy targets using cold isostatic pressing and liquid phase sintering, employing cold isostatic pressing followed by vacuum pressureless sintering. Although this process uses liquid phase sintering, the pressureless sintering driving force is limited, easily generating internal closed pores and making it difficult to ensure high density of the target material.

[0009] Hot isostatic pressing (HIP) liquid phase sintering technology combines the isotropic high pressure of HIP with the mass transfer advantages of liquid phase sintering: when the temperature reaches the liquid phase formation temperature of low melting point components, the liquid phase promotes particle rearrangement and diffusion, and the high pressure promotes particle plastic deformation and creep, significantly enhancing the densification driving force, and can prepare alloy targets with high density and uniform microstructure. However, when applying this technology to the Cr-Cu-Ag system, the following key issues need to be addressed: (1) Determine a suitable liquid phase sintering temperature window based on the melting point characteristics of Cr-Cu-Ag; (2) Design a reasonable powder particle size distribution to improve powder density and promote uniform distribution of liquid phase; (3) Control sintering process parameters to avoid excessive loss of Cu and Ag or excessive densification of the Cr matrix leading to closed pores. Summary of the Invention

[0010] The purpose of this invention is to solve at least one technical problem in the background art and to provide a CrCuAg alloy target for antibacterial coating and its preparation method.

[0011] To achieve the above objectives, the present invention provides a CrCuAg alloy target for antibacterial coating, comprising, by mass percentage: 80-90 wt% Cr, 8-15 wt% Cu, and 2-5 wt% Ag; the target has a Cr matrix skeleton and Cu and Ag filling the pores of the Cr matrix skeleton, with a relative density >99% and an average grain size ≤100 μm.

[0012] According to one aspect of the present invention, the particle size distribution of the raw material powder of the target material satisfies: Cr powder particle size > Cu powder particle size > Ag powder particle size.

[0013] According to one aspect of the present invention, the Cr powder has a particle size of 20-30 μm, the Cu powder has an average particle size of 10 μm, and the Ag powder has an average particle size of 2 μm.

[0014] To achieve the above objectives, the present invention also provides a method for preparing the above-mentioned CrCuAg alloy target for antibacterial coating, comprising: Cr powder, Cu powder and Ag powder were mechanically ball-milled and mixed under inert gas protection to obtain a mixed powder; The mixed powder is filled into a package with a relative density ≥55%; The filled package is then subjected to vacuum thermal degassing. The cladding, which has been degassed by vacuum, is subjected to hot isostatic pressing and liquid phase sintering to obtain CrCuAg alloy target blank. The CrCuAg alloy target blank is removed to obtain the CrCuAg alloy target.

[0015] According to one aspect of the invention, the inert gas is at least one of nitrogen, argon, or helium.

[0016] According to one aspect of the invention, the mechanical ball milling is carried out in a three-dimensional mixer.

[0017] According to one aspect of the present invention, when Cr powder, Cu powder and Ag powder are mechanically ball-milled and mixed under inert gas protection, the ball-to-powder ratio is 3 to 1:1 and the mixing time is 8 to 16 hours.

[0018] According to one aspect of the invention, the temperature of the vacuum thermal degassing is 300–600°C, and the vacuum degree is ≤1×10⁻⁶. - 3 Pa, heat preservation time is 6-10 hours.

[0019] According to one aspect of the invention, the vacuum degree in the encapsulation mold after vacuum thermal degassing is less than 5.0 x 10⁻⁶. -3 Pa.

[0020] According to one aspect of the present invention, the temperature of the hot isostatic pressing liquid phase sintering is 1090-1260℃, the pressure is 90-160MPa, and the holding time is 2-6h.

[0021] According to the present invention, the present invention achieves high performance of CrCuAg alloy targets through the synergistic design of specific particle size distribution and hot isostatic pressing liquid phase sintering process, including: (1) High powder density and uniformity of composition This invention specifies a particular particle size distribution of Cr powder (20-30 μm), Cu powder (10 μm), and Ag powder (2 μm). Cr powder serves as a framework, and the combination of large and small particle sizes allows Cu and Ag powders to fill the pores within the Cr powder framework, resulting in a mixed powder packing density ≥55%. This particle size distribution, combined with a mechanical ball milling mixing process, ensures thorough and uniform mixing of the three components (Cr, Cu, and Ag), laying the foundation for the compositional uniformity of subsequent liquid-phase sintering.

[0022] (2) High density and low porosity This invention employs a hot isostatic pressing liquid phase sintering process, which pre-sintersects Cu and Ag below their melting points, resulting in a Cr skeleton with moderate density and high porosity. When the temperature rises to 1090-1260℃ (above the melting points of Cu and Ag), Cu and Ag melt to form a liquid phase, which flows into the Cr skeleton pores under high pressure, achieving densification.

[0023] (3) Fine and uniform microstructure Hot isostatic pressing liquid phase sintering inhibits abnormal grain growth, with an average grain size of ≤100μm for the target material. The microstructure is uniform, free from component segregation and brittle intermediate phases, meeting the stringent requirements for microstructure uniformity in sputtering targets.

[0024] (4) Excellent comprehensive performance and antibacterial function The Cr matrix imparts high hardness, wear resistance, and corrosion resistance to the coating; Cu and Ag work synergistically to provide long-lasting antibacterial function, with Ag ion release achieving highly efficient antibacterial activity and Cu enhancing antibacterial durability. This target material is suitable for antibacterial coating applications in high-end hardware and sanitary ware, medical devices, and public contact areas (such as elevator buttons and door handles).

[0025] (5) Process controllability and yield The coordinated control of hot isostatic pressing liquid phase sintering temperature (1090-1260℃) and pressure (90-160MPa) avoids excessive volatilization loss of Cu and Ag, resulting in target purity ≥99.9%, high yield, and suitability for large-scale production. Attached Figure Description

[0026] Figure 1 Metallographic photograph of the finished CrCuAg alloy target material in Example 1 of this invention; Figure 2 This is a photograph of the finished CrCuAg alloy target material in Example 1 of the present invention. Detailed Implementation

[0027] The invention will now be discussed with reference to exemplary embodiments. It should be understood that the described embodiments are merely intended to enable those skilled in the art to better understand and thus implement the invention, and are not intended to imply any limitation on the scope of the invention.

[0028] As used herein, the term "comprising" and its variations are to be interpreted as open-ended terms meaning "including but not limited to". The term "based on" is to be interpreted as "at least partially based on". The terms "one embodiment" and "an embodiment" are to be interpreted as "at least one embodiment".

[0029] According to one embodiment of the present invention, the CrCuAg alloy target for antibacterial coating comprises, by mass percentage: 80-90 wt% Cr powder, 8-15 wt% Cu powder, and 2-5 wt% Ag powder; the target has a Cr matrix skeleton and Cu and Ag filling the pores of the Cr matrix skeleton, with a relative density >99% and an average grain size ≤100 μm.

[0030] Furthermore, according to one embodiment of the present invention, the particle size distribution of the raw material powder of the target material satisfies: Cr powder particle size > Cu powder particle size > Ag powder particle size.

[0031] In this embodiment, the Cr powder has a particle size of 20-30 μm, the Cu powder has an average particle size of 10 μm, and the Ag powder has an average particle size of 2 μm.

[0032] Furthermore, according to one embodiment of the present invention, a method for preparing a CrCuAg alloy target for antibacterial coating includes: Cr powder, Cu powder and Ag powder were mechanically ball-milled and mixed under inert gas protection to obtain a mixed powder; The mixed powder is filled into a casing with a relative density ≥ 55% (the ratio of the bulk density of the mixed powder to the theoretical density of the corresponding material, which is calculated based on the density of each component of the CrCuAg alloy target and their proportion in the alloy). The filled package is then subjected to vacuum thermal degassing; specifically, the powder-filled package is argon-arc welded, and a degassing port is reserved on the upper end cap of the package for vacuum thermal degassing. The cladding, which has been degassed by vacuum, is subjected to hot isostatic pressing and liquid phase sintering to obtain CrCuAg alloy target blank. The outer casing of the CrCuAg alloy target blank is removed to obtain the CrCuAg alloy target; the outer casing is removed by machining to obtain the CrCuAg alloy target for sputtering.

[0033] The CrCuAg alloy target material obtained by the above preparation method has a purity of ≥99.9%, a relative density of >99%, and an average grain size of ≤100μm.

[0034] In this embodiment, the inert gas is at least one of nitrogen, argon, or helium.

[0035] In this embodiment, mechanical ball milling is performed in a three-dimensional mixer.

[0036] In this embodiment, when Cr powder, Cu powder and Ag powder are mechanically ball-milled and mixed under inert gas protection, the ball-to-material ratio is 3 to 1:1 and the mixing time is 8 to 16 hours.

[0037] In this embodiment, the temperature for vacuum thermal degassing is 300–600°C, and the vacuum degree is ≤1×10⁻⁶. -3 Pa, heat preservation time is 6-10 hours.

[0038] In this embodiment, the vacuum degree in the encapsulation mold after vacuum thermal degassing is less than 5.0 x 10⁻⁶. -3 Pa.

[0039] In this embodiment, the temperature of hot isostatic pressing liquid phase sintering is 1090-1260℃, the pressure is 90-160MPa, and the holding time is 2-6h.

[0040] According to the above-described scheme of the present invention, the present invention achieves high performance of CrCuAg alloy targets through the synergistic design of specific particle size distribution and hot isostatic pressing liquid phase sintering process, including: (1) High powder density and uniformity of composition This invention specifies a particular particle size distribution of Cr powder (20-30 μm), Cu powder (10 μm), and Ag powder (2 μm). Cr powder serves as a framework, and the combination of large and small particle sizes allows Cu and Ag powders to fill the pores within the Cr powder framework, resulting in a mixed powder packing density ≥55%. This particle size distribution, combined with a mechanical ball milling mixing process, ensures thorough and uniform mixing of the three components (Cr, Cu, and Ag), laying the foundation for the compositional uniformity of subsequent liquid-phase sintering.

[0041] (2) High density and low porosity This invention employs a hot isostatic pressing liquid phase sintering process, which pre-sintersects Cu and Ag below their melting points, resulting in a Cr skeleton with moderate density and high porosity. When the temperature rises to 1090-1260℃ (above the melting points of Cu and Ag), Cu and Ag melt to form a liquid phase, which flows into the Cr skeleton pores under high pressure, achieving densification.

[0042] (3) Fine and uniform microstructure Hot isostatic pressing liquid phase sintering inhibits abnormal grain growth, with an average grain size of ≤100μm for the target material. The microstructure is uniform, free from component segregation and brittle intermediate phases, meeting the stringent requirements for microstructure uniformity in sputtering targets.

[0043] (4) Excellent comprehensive performance and antibacterial function The Cr matrix imparts high hardness, wear resistance, and corrosion resistance to the coating; Cu and Ag work synergistically to provide long-lasting antibacterial function, with Ag ion release achieving highly efficient antibacterial activity and Cu enhancing antibacterial durability. This target material is suitable for antibacterial coating applications in high-end hardware and sanitary ware, medical devices, and public contact areas (such as elevator buttons and door handles).

[0044] (5) Process controllability and yield The coordinated control of hot isostatic pressing liquid phase sintering temperature (1090-1260℃) and pressure (90-160MPa) avoids excessive volatilization loss of Cu and Ag, resulting in target purity ≥99.9%, high yield, and suitability for large-scale production.

[0045] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely one preferred embodiment of the invention and are only used to explain the invention. They do not limit the scope of protection of the invention. All other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this invention. Example 1

[0046] The preparation method of CrCuAg alloy target material for antibacterial coating is as follows: (1) Cr powder, Cu powder and Ag powder are weighed in a mass ratio of Cr:Cu:Ag=80:15:5 and then mechanically ball-milled in a three-dimensional mixer under nitrogen protection. The ball-to-powder ratio is 2:1 and the mixing time is 8h to obtain CrCuAg mixed powder. The specifications of each raw material powder are as follows: Cr powder purity ≥99.9% and particle size 20-30μm, Cu powder purity ≥99.9% and average particle size 10μm, Ag powder purity ≥99.9% and average particle size 2μm. In this embodiment, the powder particle size is limited. By matching the large and small particle sizes, Cu powder and Ag powder are filled into the Cr powder skeleton. Combined with the corresponding powder mixing process, the high powder density and uniform composition of the mixed powder are guaranteed. (2) The uniformly mixed CrCuAg powder is filled into the casing. The filling density of the mixed powder is 58% to ensure that the shrinkage of the target material after hot isostatic pressing is small and there is no risk of the casing being torn or leaking. (3) Argon arc weld the powder-filled casing, leave a degassing port on the upper end cap, and perform vacuum thermal degassing at a temperature of 380℃ with a vacuum degree ≤1×10 -3 Pa, heat preservation time 8h; (4) The cladding that has been degassed by vacuum heat is subjected to hot isostatic pressing liquid phase sintering. The hot isostatic pressing temperature is 1090℃, the pressure is 140MPa, and the holding time is 5h. (5) The outer casing of the hot isostatic liquid phase sintered target blank is removed by mechanical processing, and then machined according to the drawings to obtain the CrCuAg alloy target for sputtering.

[0047] In this embodiment, the finished CrCuAg alloy target has a relative density of 99.2%, a uniform microstructure, and an average grain size of less than 100 μm.

[0048] Figure 1 This is a metallographic photograph of the CrCuAg alloy target material in this embodiment; Figure 2 This is a photograph of the finished CrCuAg alloy target material in this embodiment. Example 2

[0049] The preparation method of CrCuAg alloy target material for antibacterial coating is as follows: (1) Cr powder, Cu powder and Ag powder are weighed in a mass ratio of Cr:Cu:Ag=85:10:5 and then mechanically ball-milled in a three-dimensional mixer under nitrogen protection. The ball-to-powder ratio is 2:1 and the mixing time is 10h to obtain CrCuAg mixed powder. The specifications of each raw material powder are as follows: Cr powder purity ≥99.9% and particle size 20-30μm, Cu powder purity ≥99.9% and average particle size 10μm, Ag powder purity ≥99.9% and average particle size 2μm. In this embodiment, the powder particle size is limited. By matching the large and small particle sizes, Cu powder and Ag powder are filled into the Cr powder skeleton. Combined with the corresponding powder mixing process, the high powder density and uniform composition of the mixed powder are guaranteed. (2) The uniformly mixed CrCuAg powder is filled into the casing. The filling density of the mixed powder is 58% to ensure that the shrinkage of the target material after hot isostatic pressing is small and there is no risk of the casing being torn or leaking. (3) Argon arc weld the powder-filled casing, leave a degassing port on the upper end cap, and perform vacuum thermal degassing at 420℃ with a vacuum degree ≤1×10 -3 Pa, heat preservation time 8h; (4) The cladding that has been degassed by vacuum heat is subjected to hot isostatic pressing liquid phase sintering. The hot isostatic pressing temperature is 1200℃, the pressure is 140MPa, and the holding time is 3h. (5) The outer casing of the hot isostatic liquid phase sintered target blank is removed by mechanical processing, and then machined according to the drawings to obtain the CrCuAg alloy target for sputtering. In this embodiment, the finished CrCuAg alloy target has a relative density of 99.4%, a uniform microstructure, and an average grain size of less than 100 μm. Example 3

[0050] The preparation method of CrCuAg alloy target material for antibacterial coating is as follows: (1) Cr powder, Cu powder and Ag powder are weighed in a mass ratio of Cr:Cu:Ag=90:5:5 and then mechanically ball-milled in a three-dimensional mixer under nitrogen protection. The ball-to-powder ratio is 2:1 and the mixing time is 10h to obtain CrCuAg mixed powder. The specifications of each raw material powder are as follows: Cr powder purity ≥99.9% and particle size 20-30μm, Cu powder purity ≥99.9% and average particle size 10μm, Ag powder purity ≥99.9% and average particle size 2μm. In this embodiment, the powder particle size is limited. By matching the large and small particle sizes, Cu powder and Ag powder are filled into the Cr powder skeleton. Combined with the corresponding powder mixing process, the high powder density and uniform composition of the mixed powder are guaranteed. (2) The uniformly mixed CrCuAg powder is filled into the casing. The filling density of the mixed powder is 59% to ensure that the shrinkage of the target material after hot isostatic pressing is small and there is no risk of the casing being torn or leaking air. (3) Argon arc weld the powder-filled casing, leave a degassing port on the upper end cap, and perform vacuum thermal degassing at a temperature of 480℃ with a vacuum degree ≤1×10 -3 Pa, heat preservation time 8h; (4) The cladding that has been degassed by vacuum heat is subjected to hot isostatic pressing liquid phase sintering. The hot isostatic pressing temperature is 1260℃, the pressure is 140MPa, and the holding time is 2.5h. (5) The outer casing of the hot isostatic liquid phase sintered target blank is removed by mechanical processing, and then machined according to the drawings to obtain the CrCuAg alloy target for sputtering.

[0051] In this embodiment, the finished CrCuAg alloy target has a relative density of 99.5%, a uniform microstructure, and an average grain size of less than 100 μm.

[0052] CrCuAg alloy targets were prepared using hot isostatic pressing (HIP). The HIP temperature was controlled to achieve liquid-phase sintering densification of the alloy targets, resulting in a density >99% and an average grain size ≤100μm.

[0053] Comparative Example 1 This comparative example provides a CrCuAg alloy target and its preparation method. Compared with Example 1, the difference is that the hot isostatic pressing process parameters are changed from 1090℃ and 140MPa to 850℃ and 150MPa. The preparation method of CrCuAg alloy target material, the specific steps are as follows: (1) Cr powder, Cu powder and Ag powder were weighed in a mass ratio of Cr:Cu:Ag=80:15:5 and then mechanically ball-milled in a three-dimensional mixer under nitrogen protection. The ball-to-material ratio was 2:1 and the mixing time was 8h to obtain CrCuAg mixed powder. The specifications of each raw material powder were as follows: Cr powder purity ≥99.9% and particle size 20-30μm, Cu powder purity ≥99.9% and average particle size 10μm, and Ag powder purity ≥99.9% and average particle size 2μm. This comparative example limits the powder particle size and uses the matching of large and small particle sizes to fill Cu powder and Ag powder into the Cr powder skeleton. Combined with the corresponding powder mixing process, the high powder density and uniform composition of the mixed powder are guaranteed.

[0054] (2) The uniformly mixed CrCuAg powder is filled into the casing. The filling density of the mixed powder is 58% to ensure that the shrinkage of the target material after hot isostatic pressing is small and there is no risk of the casing being torn or leaking. (3) Argon arc weld the powder-filled casing, leave a degassing port on the upper end cap, and perform vacuum thermal degassing at a temperature of 380℃ with a vacuum degree ≤1×10 -3 Pa, heat preservation time 8h; (4) The cladding that has been degassed by vacuum heat is subjected to hot isostatic pressing sintering at a temperature of 850℃, a pressure of 150MPa, and a holding time of 5h. (5) Remove the outer casing from the hot isostatic pressing sintered target blank by machining, and then machine it according to the drawings to obtain the CrCuAg alloy target for sputtering. The relative density of the finished CrCuAg alloy sputtering target in this comparative example is 94.7%.

[0055] Comparative Example 2 This comparative example provides a CrCuAg alloy target and its preparation method. Compared with Example 2, the difference is that the hot isostatic pressing process parameters are changed from 1200℃ and 140MPa to 900℃ and 150MPa. The preparation method of CrCuAg alloy target material, the specific steps are as follows: (1) Cr powder, Cu powder and Ag powder were weighed in a mass ratio of Cr:Cu:Ag=85:10:5 and then mechanically ball-milled in a three-dimensional mixer under nitrogen protection. The ball-to-material ratio was 2:1 and the mixing time was 10h to obtain CrCuAg mixed powder. The specifications of each raw material powder were as follows: Cr powder purity ≥99.9% and particle size 20-30μm, Cu powder purity ≥99.9% and average particle size 10μm, and Ag powder purity ≥99.9% and average particle size 2μm. This comparative example limits the powder particle size and uses the matching of large and small particle sizes to fill Cu powder and Ag powder into the Cr powder skeleton. Combined with the corresponding powder mixing process, the high powder density and uniform composition of the mixed powder were ensured. (2) The uniformly mixed CrCuAg powder is filled into the casing. The filling density of the mixed powder is 58% to ensure that the shrinkage of the target material after hot isostatic pressing is small and there is no risk of the casing being torn or leaking. (3) Argon arc weld the powder-filled casing, leave a degassing port on the upper end cap, and perform vacuum thermal degassing at 420℃ with a vacuum degree ≤1×10 -3 Pa, heat preservation time 8h; (4) The cladding that has been degassed by vacuum heat is subjected to hot isostatic pressing sintering at a temperature of 900℃, a pressure of 150MPa, and a holding time of 3h. (5) Remove the outer casing from the hot isostatic pressing sintered target blank by machining, and then machine it according to the drawings to obtain the CrCuAg alloy target for sputtering.

[0056] The relative density of the finished CrCuAg alloy sputtering target in this comparative example is 97.4%.

[0057] Comparative Example 3 This comparative example provides a CrCuAg alloy target and its preparation method. Compared with Example 3, the difference is that the hot isostatic pressing process parameters are changed from 1260℃ and 140MPa to 950℃ and 150MPa. The preparation method of CrCuAg alloy target material, the specific steps are as follows: (1) Cr powder, Cu powder and Ag powder were weighed in a mass ratio of Cr:Cu:Ag=90:5:5 and then mechanically ball-milled in a three-dimensional mixer under nitrogen protection. The ball-to-powder ratio was 2:1 and the mixing time was 10h to obtain CrCuAg mixed powder. The specifications of each raw material powder were as follows: Cr powder purity ≥99.9% and particle size 20-30μm, Cu powder purity ≥99.9% and average particle size 10μm, and Ag powder purity ≥99.9% and average particle size 2μm. This comparative example limits the powder particle size and uses the matching of large and small particle sizes to fill Cu powder and Ag powder into the Cr powder skeleton. Combined with the corresponding powder mixing process, the high powder density and uniform composition of the mixed powder are guaranteed.

[0058] (2) The uniformly mixed CrCuAg powder is filled into the casing. The filling density of the mixed powder is 59% to ensure that the shrinkage of the target material after hot isostatic pressing is small and there is no risk of the casing being torn or leaking air. (3) Argon arc weld the powder-filled casing, leave a degassing port on the upper end cap, and perform vacuum thermal degassing at a temperature of 480℃ with a vacuum degree ≤1×10 -3 Pa, heat preservation time 8h; (4) The cladding that has been degassed by vacuum heat is subjected to hot isostatic pressing sintering at a temperature of 950℃, a pressure of 150MPa, and a holding time of 2.5h. (5) Remove the outer casing from the hot isostatic pressing sintered target blank by machining, and then machine it according to the drawings to obtain the CrCuAg alloy target for sputtering.

[0059] The relative density of the finished CrCuAg alloy sputtering target in this comparative example is 98.5%.

[0060] Table 1. Comparison of process parameters and performance between the examples and comparative examples In summary, as shown in Table 1, the CrCuAg alloy target material of this invention utilizes Cr powder, Cu powder, and Ag powder with specific particle sizes. By matching the particle sizes, Cu powder and Ag powder fill the Cr powder skeleton, resulting in a high powder density in the mixed CrCuAg powder. Combined with the powder mixing process, this ensures thorough mixing of the Cr, Cu, and Ag powders, yielding a uniformly composed CrCuAg mixed powder. The CrCuAg alloy target material was prepared using hot isostatic pressing (HIP). By controlling the HIP temperature, liquid-phase sintering densification of the alloy target material was achieved, resulting in a target density >99% and an average grain size ≤100 μm.

[0061] The above description is merely a preferred embodiment of this application and an explanation of the technical principles employed. Those skilled in the art should understand that the scope of the invention involved in this application is not limited to technical solutions formed by specific combinations of the above-described technical features, but should also cover other technical solutions formed by arbitrary combinations of the above-described technical features or their equivalents without departing from the inventive concept. For example, technical solutions formed by substituting the above-described features with (but not limited to) technical features with similar functions disclosed in this application.

[0062] It should be understood that the sequence number of each step in the invention and its embodiments does not absolutely imply the order of execution. 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 invention.

Claims

1. A CrCuAg alloy target for antibacterial coating, characterized in that, The target material comprises, by mass percentage: 80-90 wt% Cr, 8-15 wt% Cu, and 2-5 wt% Ag; the target material has a Cr matrix framework and Cu and Ag filling the pores of the Cr matrix framework, with a relative density >99% and an average grain size ≤100 μm.

2. The CrCuAg alloy target for antibacterial coating according to claim 1, characterized in that, The particle size distribution of the raw material powder of the target material satisfies: Cr powder particle size > Cu powder particle size > Ag powder particle size.

3. The CrCuAg alloy target for antibacterial coating according to claim 2, characterized in that, The Cr powder has a particle size of 20-30 μm, the Cu powder has an average particle size of 10 μm, and the Ag powder has an average particle size of 2 μm.

4. The method for preparing the CrCuAg alloy target for antibacterial coating according to any one of claims 1-3, characterized in that, include: Cr powder, Cu powder and Ag powder were mechanically ball-milled and mixed under inert gas protection to obtain a mixed powder; The mixed powder is filled into a package with a relative density ≥55%; The filled package is then subjected to vacuum thermal degassing. The cladding, which has been degassed by vacuum, is subjected to hot isostatic pressing and liquid phase sintering to obtain CrCuAg alloy target blank. The CrCuAg alloy target blank is removed to obtain the CrCuAg alloy target.

5. The preparation method according to claim 4, characterized in that, The inert gas is at least one of nitrogen, argon, or helium.

6. The preparation method according to claim 4, characterized in that, The mechanical ball milling is carried out in a three-dimensional mixer.

7. The preparation method according to claim 4, characterized in that, When Cr powder, Cu powder and Ag powder are mechanically ball-milled and mixed under inert gas protection, the ball-to-powder ratio is 3 to 1:1 and the mixing time is 8 to 16 hours.

8. The preparation method according to claim 4, characterized in that, The vacuum thermal degassing temperature is 300–600℃, and the vacuum degree is ≤1×10⁻⁶. -3 Pa, heat preservation time is 6-10 hours.

9. The preparation method according to claim 4, characterized in that, The vacuum degree in the encapsulation mold after vacuum thermal degassing is less than 5.0 x 10⁻⁶. -3 Pa.

10. The preparation method according to claim 4, characterized in that, The hot isostatic pressing liquid phase sintering temperature is 1090-1260℃, the pressure is 90-160MPa, and the holding time is 2-6h.

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