Microstructure, mechanical properties and corrosion resistance of CuZrY/Al, Ti, Hf series high-entropy alloys
Microstructure, mechanical properties and corrosion resistance of CuZrY/Al, Ti, Hf series high-entropy alloys
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DOI：
10.1016/j.matdes.2016.06.100
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发表时间：
2016-10
影响因子：
8.4
通讯作者：
Zitang Zhang;E. Axinte;W. Ge;Caiyun Shang;Y. Wang
中科院分区：
文献类型：
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作者：
Zitang Zhang;E. Axinte;W. Ge;Caiyun Shang;Y. Wang
采用电弧熔炼法制备了一系列高熵合金CuYZrTiHf（Z1）、CuYZrAlHf（Z2）和CuYZrAlTi（Z3）。所有这些HEAs主要由六方密排（hcp）树枝晶和CuY型体心立方（bcc）枝晶间相组成。结果表明，具有六方晶系结构的主元素和合适的原子尺寸有利于六方晶系枝晶的形成。特别是在Z3 HEA中出现了少量的非晶相，这与熔体粘度的增加和用于制备大块金属玻璃的主要元素有关。Z1的抗压强度和塑性应变分别为1340 MPa和13.2%，表明塑性断裂。Z_2和Z_3型高性能铝合金具有较高的维氏硬度和抗压强度，但塑性严重下降。在海水溶液中进行了电化学腐蚀测试，结果表明，Z1和Z2型换热器具有较好的耐腐蚀性能，Z3型换热器具有较好的耐点蚀性能。腐蚀形貌观察表明，枝晶间含有CuY型相的区域有利于优先腐蚀。
A series of high-entropy alloys (HEAs) CuYZrTiHf (Z1), CuYZrAlHf (Z2) and CuYZrAlTi (Z3) were prepared by arc melting. All these HEAs mainly consist of hexagonal close-packed (hcp) dendrites and CuY-type body-centered cubic (bcc) interdendrite phases. The result affirmed that principal elements with hcp structure and suitable atomic size are beneficial to the formation of hcp dendrites. Specially, small content of amorphous phase appears in Z3 HEA, which is related to the increased melt viscosity and principal elements used for preparing bulk metallic glasses. The compressive strength and plastic strain of Z1 are 1340 MPa and 13.2%, indicating a plastic fracture. Z2 and Z3 HEAs have higher Vickers hardness and compressive strength but the plasticity is severely depressed. The electrochemical corrosion measurements in the seawater solution were carried on. Z1 and Z2 HEAs possess better corrosion resistance and Z3 has a higher pitting resistance. According to the observation of corrosion morphologies, the interdendritic region containing CuY-type phase is feasible to preferential corrosion.