退火温度对Al-Co-Fe-Ni共晶高熵合金组织性能的影响  

Effect of Annealing Temperature on the Microstructure and Properties of Al-Co-Fe-Ni Eutectic High-entropy Alloy

作　　者：聂帅 刘浩翔 武宇浩 刘栩东 贺一轩 王军[1] 李金山[1] NIE Shuai;LIU Haoxiang;WU Yuhao;LIU Xudong;HE Yixuan;WANG Jun;LI Jinshan(State Key Laboratory of Solidification Processing,Northwestern Polytechnical University,Xi'an 710072,China;Collaborative Innovation Center of NPU,Shanghai 201108,China;Center of Advanced Lubrication and Seal Materials,Northwestern Polytechnical University,Xi'an 710072,China)

机构地区：[1]西北工业大学凝固技术国家重点实验室,陕西西安710072 [2]西北工业大学上海闵行协同创新中心,上海201108 [3]西北工业大学先进密封材料与润滑研究中心,陕西西安710072

出　　处：《铸造技术》2024年第7期639-646,共8页Foundry Technology

基　　金：上海市扬帆计划(21YF1450800);西安市科协青年人才托举计划(W021009)。

摘　　要：良好的延展性是合金成形能力的重要影响因素,尽管共晶高熵合金具有良好的铸造性能,但有限的延展性限制了其实际应用。本文采用热轧和退火工艺来克服共晶高熵合金这一问题,探究热轧后不同退火温度对Al21.5Co19.5Fe9.5Ni50共晶高熵合金微观组织和力学性能的影响。结果表明,当退火温度为700℃时,合金的断裂强度和断裂伸长率达到最优,分别为1211 MPa和14%。其优异强塑性匹配来自于热轧-700样品在拉伸变形过程中,FCC相内出现大量位错并在相界面处堆积,B2相由于相界面处的高局部应力导致应力诱发马氏体相变转变L10孪晶马氏体,合金产生了TRIP效应,使其达到最优的强塑性匹配。Excellent ductility is a critical factor influencing the formability of alloys.While eutectic high-entropy alloys exhibit good casting performance,their limited ductility limits their practical application.Therefore,hot rolling and annealing processes were utilized to address the ductility issue of eutectic high-entropy alloys,and the impact of different annealing temperatures following hot rolling on the microstructure and mechanical properties of the Al21.5Co19.5Fe9.5Ni50 eutectic high-entropy alloy was investigated.The findings indicate that at an annealing temperature of 700℃,the alloy achieves optimal fracture strength and elongation at break values of 1211 MPa and 14%,respectively.The superior strength and plasticity combination is attributed to the emergence of a significant number of dislocations in the FCC phase and their accumulation at the phase interface during the tensile deformation process of the hot-rolled 700 sample.The high local stress at the phase interface in the B2 phase induces stress-induced martensitic transformation into L10 twin martensite,enabling the alloy to exhibit a TRIP effect,thereby achieving an optimal strength and plasticity balance.

关 键 词：共晶高熵合金 退火温度 力学性能 相变表征 变形机制 

分 类 号：TG139[一般工业技术—材料科学与工程]