Short-term oxidation behavior of powder metallurgy Al_(0.8)Co_(0.5)Cr_(1.5)CuFeNi HEA in high-temperature solid and semi-solid intervals  

作　　者：Minjie Huang Jufu Jiang Ying Wang Yingze Liu Ying Zhang Jian Dong 

机构地区：[1]School of Materials Science and Engineering,Harbin Institute of Technology,Harbin 150001,China [2]School of Mechatronics Engineering,Harbin Institute of Technology,Harbin 150001,China

出　　处：《Journal of Materials Science & Technology》2024年第26期116-131,共16页材料科学技术(英文版)

基　　金：supported by the National Natural Science Foun-dation of China(NSFC)under Grant No.52071113.

摘　　要：In this work,possible short-term thermal exposure oxidation in hot processing including semi-solid processing is focused.We aim to investigate the short-term oxidation behavior of a novel powder metallurgy Al_(0.8)Co_(0.5)Cr_(1.5)CuFeNi high entropy alloy(HEA)in high-temperature solid(1000-1100℃)and semi-solid(1125-1225℃)intervals.From 1000 to 1225℃,mass gain increases from 0.31 to 0.45 mg cm^(-2)after 60 min oxidation,presenting superior oxidation resistance in the semi-solid state compared with other semi-solid alloys.Equiaxedα-Al_(2)O_(3)grains are the predominant component of oxide scales and no obvious internal oxidation layer occurs in both solid and semi-solid intervals.Al_(2)O_(3)scale growth is predominantly determined by outward Al^(3+)diffusion.For solid oxidation,different scale formation kinetics occur on various phases and the BCC(B2)phase has faster scale formation kinetics.This is attributed to outward Al^(3+)diffusion rate differences in various component systems.During semi-solid oxidation,the increased degree of chaos and number of vacancies in the liquid phase provide a diffusion channel,leading to rapid Al_(2)O_(3)formation.Oxidation resistance in the semi-solid state is attributed to dense Al_(2)O_(3)scales formed through selective oxidation of Al.

关 键 词：High entropy alloy Short-term oxidation Semi-solid interval Oxidation behavior Oxidation resistance 

分 类 号：TG1[金属学及工艺—金属学]