W-v-cr-ti-ta near-equiatomic high-entropy alloy thin film and preparation method thereof

Abstract

This invention discloses a W-V-Cr-Ti-Ta near-equal atomic ratio high-entropy alloy thin film and its preparation method, belonging to the field of high-entropy alloy thin film technology. The preparation method employs magnetron sputtering deposition, using a first circular target composed of Ta and W, a second circular target composed of Ti and V, and a third circular target composed of Cr, with the area ratio of Ta, W, Ti, V, and Cr being 1:1:1:1:2. This invention proposes a method for preparing W-V-Cr-Ti-Ta near-equal atomic ratio high-entropy alloy thin films, filling the technical gap in near-equal atomic ratio thin films in the prior art and providing a feasible solution for the preparation of such thin films.

Description

Technical Field

[0001] This invention relates to the field of high-entropy alloy thin film technology, and in particular to a WV-Cr-Ti-Ta near-equal atomic ratio high-entropy alloy thin film and its preparation method. Background Technology

[0002] Neutron targets need to withstand high-flux irradiation and high temperatures. WV-Cr-Ti-Ta high-entropy alloy thin films offer several advantages: the body-centered cubic structure formed by multi-principal element solid solution exhibits excellent radiation resistance; the synergistic effect of various elements can achieve high neutron yield, low activation, high-temperature strength, and oxidation resistance; and the film morphology can further enhance radiation resistance through nano-interfaces. However, if the content of various components in the film is uneven, it will lead to a significant decrease in local neutron yield and concentrated distribution of irradiation damage, thereby causing thermal instability and restricting the normal performance of the film. Therefore, it is necessary to develop a method for preparing WV-Cr-Ti-Ta near-equal atomic ratio high-entropy alloy thin films. Summary of the Invention

[0003] To address the aforementioned technical problems, this invention provides a WV-Cr-Ti-Ta near-equal atomic ratio high-entropy alloy thin film and its preparation method.

[0004] To achieve the above objectives, the present invention adopts the following technical solution:

[0005] A method for preparing a WV-Cr-Ti-Ta near-equal atomic ratio high-entropy alloy thin film, the constituent elements of which are W, V, Cr, Ti and Ta; the preparation method adopts magnetron sputtering deposition, and the targets used are a first circular target composed of Ta and W, a second circular target composed of Ti and V and a third circular target composed of only Cr, and the area ratio of Ta, W, Ti, V and Cr is 1:1:1:1:2.

[0006] The power of the first circular target is set to 200W, the power of the second circular target is set to 266W, and the power of the third circular target is set to 60W.

[0007] The preparation method specifically includes the following steps:

[0008] S1: Evacuate the coating cavity to a vacuum level not exceeding 1×10⁻⁶. -4 Pa, argon gas is introduced; the argon gas flow rate is 15~450 sccm;

[0009] S2: Set the sputtering power of several circular targets in a constant pressure manner;

[0010] S3: Start magnetron sputtering to deposit a film on the substrate.

[0011] The three circular targets are arranged in a symmetrical arrangement around the central sample stage, with the three targets mounted on the same horizontal circumference and in an equilateral triangle shape. They are all tilted toward the central sample stage, forming a three-dimensional oblique symmetrical arrangement in the deposition chamber.

[0012] During the preparation process, the gas pressure inside the coating cavity is maintained at 0.55Pa~0.6Pa, and the temperature is maintained at 115℃~125℃.

[0013] The process includes cleaning the target surface before coating.

[0014] A WV-Cr-Ti-Ta near-equal atomic ratio high entropy alloy thin film is prepared by the above-mentioned preparation method of near-equal atomic ratio high entropy alloy thin film, and the content deviation of each element in the near-equal atomic ratio high entropy alloy thin film is no greater than ±2at.

[0015] Among them, the WV-Cr-Ti-Ta near-equal atomic ratio high-entropy alloy thin film has a body-centered cubic single-phase solid solution structure.

[0016] The beneficial effects of this invention are as follows:

[0017] (1) This invention proposes a method for preparing WV-Cr-Ti-Ta near-equal atomic ratio high-entropy alloy thin films, which fills the technical gap of near-equal atomic ratio in the prior art and provides a feasible solution for the preparation of thin films of this system.

[0018] (2) The present invention has strong process stability and operability, good process repeatability, and is easy to promote and apply in engineering.

[0019] (3) The preparation technology can be used to obtain high-entropy alloy thin films with near-equal atomic ratios of WV-Cr-Ti-Ta elements, which can solve the problems of local neutron yield reduction and concentrated distribution of irradiation damage caused by uneven atomic ratio, thus leading to thermal instability, and improve the performance of WV-Cr-Ti-Ta high-entropy alloy thin films. Attached Figure Description

[0020] Figure 1 This is a schematic diagram of the first circular target in Example 1.

[0021] Figure 2 This is a schematic diagram of the second circular target in Example 1.

[0022] Figure 3 This is a schematic diagram of the third circular target in Example 1.

[0023] Figure 4 The image shows the cross-sectional SEM morphology of the WV-Cr-Ti-Ta near-equal atomic ratio high-entropy alloy thin film prepared in Example 1.

[0024] Figure 5 The image shows the surface distribution of V in the near-equal atomic ratio WV-Cr-Ti-Ta high-entropy alloy thin film prepared in Example 1 (EDS diagram).

[0025] Figure 6 The image shows the surface distribution of W in the near-equal atomic ratio WV-Cr-Ti-Ta high-entropy alloy thin film prepared in Example 1 (EDS diagram).

[0026] Figure 7 The image shows the surface distribution of Cr in the near-equal atomic ratio WV-Cr-Ti-Ta high-entropy alloy thin film prepared in Example 1 (EDS diagram).

[0027] Figure 8 EDS diagram of the surface distribution of Ti element in the near-equal atomic ratio WV-Cr-Ti-Ta high-entropy alloy thin film prepared in Example 1.

[0028] Figure 9 The image shows the surface distribution of Ta in the near-equal atomic ratio WV-Cr-Ti-Ta high-entropy alloy thin film prepared in Example 1 (EDS diagram). Detailed Implementation

[0029] 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 illustrative and not intended to limit the invention. Furthermore, the technical features involved in the various embodiments of this invention described below can be combined with each other as long as they do not conflict with each other.

[0030] Example 1:

[0031] This embodiment provides a method for preparing a near-equal atomic ratio WV-Cr-Ti-Ta high-entropy alloy thin film. Specifically, magnetron sputtering deposition is used. The deposition employs three circular targets, each with a diameter of 75 mm, wherein the first circular target is as follows... Figure 1 The Ta-W composite target shown has a 1:1 area ratio of Ta and W. The second circular target is as follows. Figure 2 The Ti-V composite target shown has an area ratio of Ti to V of 1:1. The third circular target is as follows. Figure 3 The Cr target shown is arranged in the deposition chamber with the first, second, and third circular targets mounted on the same horizontal circumference with the central sample stage as the center. From a top-down view, the angle between each pair of targets is 120° (forming an equilateral triangle distribution). All targets are tilted towards the central sample stage, forming a symmetrical, three-dimensional arrangement around the deposition chamber.

[0032] Specifically, Figure 1 This is a schematic diagram of the first circular target in Example 1, where the area ratio of Ta and W elements in the first circular target is 1:1. Figure 2 This is a schematic diagram of the second circular target in Example 1, where the area ratio of Ti and V in the second circular target is 1:1. Figure 3 This is a schematic diagram of the third circular target in Example 1. The third circular target contains only Cr.

[0033] The preparation method in this embodiment specifically includes the following steps:

[0034] (1) Evacuate the cavity for coating to 1×10 -4 Pa, argon gas is introduced at a flow rate of 450 sccm;

[0035] (2) Set the voltage to 1500V, introduce argon gas at a flow rate of 15sccm, and clean the surface of the target material for ten minutes;

[0036] (3) Set the power of the first circular target to 200 watts, the power of the second circular target to 266 watts, and the power of the third circular target to 60 watts. Start the magnetron sputtering coating system and deposit a near-equal atomic ratio WV-Cr-Ti-Ta high-entropy alloy thin film on the substrate (in this embodiment, the substrate material is an oxygen-free copper block) for 30 minutes to complete the preparation of the thin film. During the coating process, the gas pressure in the cavity is maintained at 0.58 Pa and the temperature is maintained at 120°C.

[0037] Comparative Example 1:

[0038] The preparation method of Comparative Example 1 is the same as that of Example 1, except that the sputtering power of the target is different. Specifically:

[0039] The power of target 1 (Ta / W) was set at 300 watts, target 2 (Ti / V) at 216 watts, and target 3 (Cr) at 60 watts.

[0040] After coating, EDS measurements showed that the atomic percentages of W, Cr, Ta, V, and Ti in the prepared film were 27.07 at%, 19.1 at%, 26.39 at%, 14.72 at%, and 12.7 at%, respectively. The atomic percentage of target 1 (Ta / W) was too high (significantly higher than 20 at%), the atomic percentage of target 2 (Ti / V) was significantly lower than 20 at%, and the power of target 3 (Cr) was close to 20 at%. Therefore, the power of target 1 was reduced by 50 W to increase the proportions of Cr, Ti, and V.

[0041] Comparative Example 2:

[0042] The preparation method of Comparative Example 2 is the same as that of Example 1, except that the sputtering power of the target is different. Specifically:

[0043] The power of target 1 (Ta / W) was 250 watts, the power of target 2 (Ti / V) was 216 watts, and the power of target 3 (Cr) was 60 watts. Other parameters and procedures remained unchanged.

[0044] After coating at the specified power, the atomic percentages of W, Cr, Ta, V, and Ti in the prepared film, measured by EDS, were 23.93 at%, 22.4 at%, 23.89 at%, 16.31 at%, and 13.48 at%, respectively. The atomic percentage of target 1 (Ta / W) was too high (above 20 at%, but lower than in the first experiment), while the power of target 3 (Cr) was below 20 at%. Therefore, the power of target 1 was further reduced by 50 watts to decrease the percentages of Ta and W.

[0045] Comparative Example 3:

[0046] The preparation method of Comparative Example 3 is the same as that of Example 1, except that the sputtering power of the target is different. Specifically:

[0047] The power of target 1 (Ta / W) was 200 W, target 2 (Ti / V) was 216 W, and target 3 (Cr) was 60 W, with other parameters and procedures remaining unchanged. After deposition at these power levels, the atomic percentages of W, Cr, Ta, V, and Ti in the prepared film, measured by EDS, were 22.8 at%, 24.1 at%, 22.5 at%, 16.7 at%, and 13.9 at%, respectively. The atomic percentage of target 1 (Ta / W) was slightly higher than 20 at%, while the atomic percentage of target 3 (Cr) was significantly higher than 20 at%. Therefore, the power of target 2 was increased by 50 W to improve the proportions of V and Ti.

[0048] Figure 4 The image shows a cross-sectional SEM image of the near-equal atomic ratio WV-Cr-Ti-Ta high-entropy alloy thin film prepared in Example 1. Figure 4 As can be seen, the near-equal atomic ratio WV-Cr-Ti-Ta high-entropy alloy film has a uniform thickness of approximately 1 μm.

[0049] Figure 5 The image shows the surface distribution EDS diagram of the V element in the near-equal atomic ratio WV-Cr-Ti-Ta high-entropy alloy thin film obtained in Example 1. Figure 6 The image shows the surface distribution of W in the near-equal atomic ratio WV-Cr-Ti-Ta high-entropy alloy thin film obtained in Example 1 (EDS diagram). Figure 7 The image shows the surface distribution of Cr in the near-equal atomic ratio WV-Cr-Ti-Ta high-entropy alloy thin film obtained in Example 1 (EDS diagram). Figure 8 The image shows the surface distribution of Ti in the near-equal atomic ratio WV-Cr-Ti-Ta high-entropy alloy thin film obtained in Example 1 (EDS diagram). Figure 9The image shows the surface distribution EDS plot of Ta element in the near-equal atomic ratio WV-Cr-Ti-Ta high-entropy alloy thin film obtained in Example 1. From... Figures 5 to 9 In the near-equal atomic ratio WV-Cr-Ti-Ta high-entropy alloy thin film prepared in this embodiment, the atomic percentages of W, Cr, Ta, V, and Ti are 21.3at%, 20.3at%, 20.3at%, 19.9at%, and 18.2at%, respectively. The content of each element is close to the equal atomic ratio, thus achieving a near-equal atomic ratio composition distribution.

[0050] Those skilled in the art will readily understand that the above description is merely a preferred embodiment of the present invention. The above embodiments are provided only for the purpose of describing the present invention and are not intended to limit the present invention. Parts not described in detail in this specification are well-known in the art and are not intended to limit the scope of the present invention. The scope of the present invention is defined by the appended claims. All equivalent substitutions and modifications made without departing from the spirit and principle of the present invention should be covered within the scope of the present invention.

Claims

1. A method for preparing a WV-Cr-Ti-Ta near-equal atomic ratio high-entropy alloy thin film, characterized in that, The WV-Cr-Ti-Ta near-equal atomic ratio high-entropy alloy thin film is composed of five elements: W, V, Cr, Ti, and Ta. The preparation method adopts magnetron sputtering deposition, and the targets used are a first circular target composed of Ta and W, a second circular target composed of Ti and V, and a third circular target composed of only Cr. The area ratio of Ta, W, Ti, V, and Cr is 1:1:1:1:

2.

2. The method for preparing WV-Cr-Ti-Ta near-equal atomic ratio high-entropy alloy thin films according to claim 1, characterized in that, The power of the first circular target is set to 200W, the power of the second circular target is set to 266W, and the power of the third circular target is set to 60W.

3. The method for preparing WV-Cr-Ti-Ta near-equal atomic ratio high-entropy alloy thin films according to claim 2, characterized in that, The preparation method specifically includes the following steps: S1: Evacuate the coating cavity to a vacuum level not exceeding 1×10⁻ 4 Pa, argon gas is introduced; S2: Set the sputtering power of several circular targets in a constant pressure manner; S3: Start magnetron sputtering to deposit a film on the substrate.

4. The method for preparing WV-Cr-Ti-Ta near-equal atomic ratio high-entropy alloy thin films according to claim 3, characterized in that, Three circular targets are arranged in a symmetrical, three-dimensional arrangement around the central sample stage, with the three targets mounted on the same horizontal circumference and forming an equilateral triangle. All three targets are tilted toward the central sample stage.

5. The method for preparing WV-Cr-Ti-Ta near-equal atomic ratio high-entropy alloy thin films according to claim 4, characterized in that, During the preparation process, the gas pressure inside the coating cavity is maintained at 0.55Pa~0.6Pa, and the temperature is maintained at 115℃~125℃.

6. The method for preparing WV-Cr-Ti-Ta near-equal atomic ratio high-entropy alloy thin films according to claim 5, characterized in that, The process also includes cleaning the target surface before coating.

7. A WV-Cr-Ti-Ta near-equal atomic ratio high-entropy alloy thin film, characterized in that, The near-equal atomic ratio high entropy alloy thin film is prepared by the preparation method of any one of claims 2 to 6, and the content deviation of each element in the near-equal atomic ratio high entropy alloy thin film is no greater than ±2at.

8. The WV-Cr-Ti-Ta near-equal atomic ratio high-entropy alloy thin film according to claim 7, characterized in that, WV-Cr-Ti-Ta near-equal atomic ratio high-entropy alloy thin films have a body-centered cubic single-phase solid solution structure.

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