JIANG Yue, ZHOU Guang-tai, CHENG Si-meng, et al. Study on Microstructure and Properties of CrFeCoNiTix High-Entropy Alloy[J]. 2020, 25(6): 112-118.DOI: 10.15938/j.jhust.2020.06.016.
摘 要: 为了研究 Ti 含量对高熵合金组织结构和性能的影响,采用粉末冶金法制备了 CrFe-CoNiTix 高熵合金。采用 XRD、SEM、EDS、金相显微镜等测试技术,分析高熵合金显微组织,用硬度 计测试了显微维氏硬度,并研究了 CrFeCoNiTix 高熵合金在 3. 5wt% NaCl 溶液中的电化学腐蚀性 能。结果表明: CrFeCoNiTix 高熵合金主要为 FCC 相,随 Ti 元素添加量的增加,高熵合金的晶格畸 变严重,枝晶间处的固溶相( B 相、L 相) 逐渐增多; 同时,随着 Ti 元素添加量的增加,高熵合金由单 相组织转变为枝晶和枝晶间两相组织; 合金的枝晶区域富含 Fe、Co、Ni 元素,枝晶间区域富含 Ti 元 素,Cr 元素较为均匀的分布在基体上。合金的维氏硬度值随 Ti 含量的增加呈现逐渐增加的趋势, 当 x = 1. 0 时合金的硬度最高,为 643. 8 HV; CrFeCoNiTi0. 6高熵合金具有最佳耐腐蚀性能。
Abstract
In order to study the variation of Ti content on the microstructure and properties of the high entropyentropy alloy was analyzed by XRD,SEM,EDS and metallographic microscope. The micro Vickers hardness of the high - entropy alloy was tested with Vickers hardness tester. The electrochemical corrosion performance of CrFeCoNiTix high - entropy alloy in 3. 5wt% NaCl solution was also studied. The results showed that CrFeCoNiTix high - entropy alloy was mainly composed of FCC phase structure. With the increase of Ti element addition,the lattice distortion of the high - entropy alloy increases,and the solid solution phase ( B phase,L phase) in the interdendritic area gradually increases. And the high - entropy alloy was transformed from single - phase structure to dendrite and interdendrite two - phase structure due to the increase of Ti element addition amount. The dendrite area of the alloy is rich in Fe,Co,Ni elements,the interdendritic area is rich in Ti element,and the Cr element is more evenly distributed in the alloy matrix. The vickers hardness value of the alloy showed a gradually increasing trend with the increase of Ti content. When x = 1. 0,the hardness of the alloy reached the maximum value of 643. 8 HV. CrFeCoNiTi0. 6 high - entropy alloy has better corrosion resistance