放电等离子烧结AlCoCrFeNi_(2.1)共晶高熵合金的组织演变与性能调控  

Microstructure Evolution and Control of Mechanical Properties of AlCoCrFeNi_(2.1)Eutectic High-entropy Alloys Prepared by Spark Plasma Sintering

作　　者：兰利伟 崔泽琴[1] 王文先[1] 郝晓虎 LAN Liwei;CUI Zeqin;WANG Wenxian;HAO Xiaohu(College of Materials Science and Engineering,Taiyuan University of Technology,Taiyuan 030024,China)

机构地区：[1]太原理工大学材料科学与工程学院,太原030024

出　　处：《太原理工大学学报》2022年第5期793-799,共7页Journal of Taiyuan University of Technology

基　　金：国家自然科学基金资助项目(52075360,52105389)。

摘　　要：采用放电等离子烧结(SPS)技术在恒压40 MPa下选择不同的烧结温度(900,1000,1100,1200℃)制备AlCoCrFeNi_(2.1)共晶高熵合金(EHEAs),研究温度对EHEAs致密化行为、物相组成、宏观形貌与微观组织以及不同截面力学性能的影响规律。随着烧结温度的升高,合金的孔隙缺陷逐渐消失,当烧结温度为1200℃时致密度高达99.2%.SPS烧结EHEAs的微观组织为树枝晶,物相由FCC和BCC/B2相组成,并分别分布于枝晶和枝晶间。SPS低温烧结状态下由于孔隙效应显示出压缩性能的各向异性,随着温度的升高,各向异性消失。烧结温度为1200℃时抗压强度最高可达2690 MPa,延伸率为40%.AlCoCrFeNi_(2.1) eutectic high-entropy alloys(EHEAs)were prepared by spark plasma sintering(SPS)technology at different sintering temperatures(900,1000,1100,1200℃)at a constant pressure of 40 MPa.The effects of temperature on the densification behavior,phase composition,macroscopic morphology and microstructure,and mechanical properties at different sections of EHEAs were studied.As the sintering temperature increases,the pore defects of the alloy gradually disappear,and the highest density can reach 99.2%(sintered at 1200℃).The microstructure of SPS sintered alloy is dendrite,and its phase is composed of FCC and BCC/B2 phases,which are distributed in dendrites and interdendrites,respectively.The SPS sintered samples show anisotropy in compressive properties due to porosity effect in the low-temperature sintered state,and the anisotropy disappears with the increase of temperature.At 1200℃,the strength is the highest,up to 2690 MPa,and the plasticity reaches about 40%.

关 键 词：放电等离子烧结 共晶高熵合金 微观组织 力学性能 

分 类 号：TB331[一般工业技术—材料科学与工程]