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.
作者
聂帅
刘浩翔
武宇浩
刘栩东
贺一轩
王军
李金山
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)
出处
《铸造技术》
CAS
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)。
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
eutectic high-entropy alloy
annealing temperature
mechanical properties
phase transformation characteri-stics
deformation mechanism
作者简介
聂帅,2001年生,硕士生.研究方向为高熵合金、力学性能研究、机器学习.Email:snie@mail.nwpu.edu.cn;通讯作者:贺一轩,1990年生,博士,副教授.研究方向为过冷凝固、金属熔体结构、磁场调控合金组织性能、共晶高熵合金等.Email:yxhe@nwpu.edu.cn。
