钨表面WTaTiVCr高熵合金层的组织与性能

使用双辉等离子体渗金属技术,通过调整渗金属温度在钨表面制备了WTaTiVCr高熵合金层,使用扫描电镜(SEM)、X射线能谱分析(EDS)、X射线衍射(XRD)、显微硬度计、往复摩擦试验和电化学腐蚀试验等对其组织成分、力学性能、耐磨性和耐蚀性等进行了分析。结果表明:当渗金属温度为1150 ℃、源极与阴极电压差为400 V时,可以得到含有扩散层、沉积层的复合渗金属层,其中扩散层区域各元素的原子分数为W_0.38Ta_0.14Ti_0.2V_0.2Cr_0.08,相结构为单相BCC结构,符合高熵合金层的相结构与元素组成规律。同时其表面硬度由于受到固溶强化、晶格畸变等强化机理,与纯钨相比有很大的提升,达到1300 HV0.2以上。另外,该渗金属层的平均摩擦因数为0.447,磨损率为3.43×10^-8 mm³/(N·mm),腐蚀速率为3.87 mg/(m²·h),具备一定的耐磨性和耐蚀性。综合以上结果,通过双辉技术在钨表面制备的WTaTiVCr高熵合金层可以有效提高W基体的力学性能和耐腐蚀性能。

Microstructure and properties of WTaTiVCr high-entropy alloy layer on tungsten surface

WTaTiVCr high-entropy alloy composite metalized layer on the surface of tungsten was prepared by using double-glow plasma metalizing technology and adjusting the metalizing temperature, then the microstructure composition, mechanical properties, wear resistance and corrosion resistance of the metalized layer were analyzed by means of SEM, EDS, XRD, microhardness tester, reciprocating friction test and electrochemical corrosion test. The results show that when the metalizing temperature is 1150 ℃ and the voltage difference between the source and the cathode is 400 V, a composite metalized layer containing a diffusion layer and a deposition layer can be obtained, and the atomic fraction of each element in the diffusion layer area is W_0.38Ta_0.14Ti_0.2V_0.2Cr_0.08, where the phase structure is a single-phase BCC structure, that meets the requirements of high-entropy alloys. At the same time, the surface hardness of the metalized layer reaches about 1400 HV0.2, which is greatly improved compared to pure tungsten due to the strengthening mechanisms of solid solution strengthening and lattice distortion. In addition, the average friction coefficient of the metalized layer is 0.447, the wear rate is 3.43×10^-8 mm³/(N·mm), and the corrosion rate is 3.87 mg/(m²·h), which possesses a certain degree of wear resistance and corrosion resistance. In summary, the WTaTiVCr high-entropy alloy layer prepared by double-glow technology on the surface of tungsten can effectively improve the mechanical properties and corrosion resistance of the W substrate.