Sensitivity of the Impact Toughness and Microstructure of 15CrNi3MoV Steel Under Different Quenching Rates  

作　　者：Bing Wang Hong-Lin Zhang Bin Xu Hai-Yang Jiang Ming-Yue Sun Dian-Zhong Li 

机构地区：[1]Key Laboratory of Nuclear Materials and Safety Assessment,Institute of Metal Research,Chinese Academy of Sciences,Shenyang,110016,China [2]School of Materials Science and Engineering,University of Science and Technology of China,Shenyang,110016,China [3]Shenyang National Laboratory for Materials Science,Institute of Metal Research,Chinese Academy of Sciences,Shenyang,110016,China

出　　处：《Acta Metallurgica Sinica(English Letters)》2023年第10期1735-1748,共14页金属学报（英文版）

基　　金：supported by the National Key Research and Development Program(Grant No.2018YFA0702900);the National Natural Science Foundation of China(Grant Nos.52173305,52101061,52233017,52203384);the China Postdoctoral Science Foundation(Grant Nos.2020M681004,2021M703276);the Institute of Metal Research Innovation Foundation(Grant No.2022-PY12);the Ling Chuang Research Project of China National Nuclear Corporation,CNNC Science Fund for Talented Young Scholars and Youth Innovation Promotion Association,Chinese Academy of Sciences.

摘　　要：The sensitivities of the mechanical properties and microstructure of 15CrNi3MoV alloy steel under different quenching rates were investigated in the present study.After subjection to quenching with four different cooling rates(water cooling,forced air cooling,static air cooling and furnace cooling)followed by tempering,the microstructure was characterized by scanning electron microscopy(SEM),electron back-scattered diffraction(EBSD),and transmission electron microscopy(TEM);and the low-temperature(−20°C)impact toughness was evaluated.The results showed that the tempered microstructure and mechanical properties had high sensitivity to the quenching rate.With a decrease in the quenching rate,the low-temperature impact energy of tempered specimens decreased with increasing fluctuation.Correspondingly,the fracture morphology changed from completely ductile to brittle.In addition,as the quenching cooling rate decreased,the as-quenched matrix changed from a lathy to a polygonal structure with the presence of carbides and martensite-austenite(M-A)constituents,and the effective grain size increased.Tempered martensite with dispersed fine carbides was found in the tempered water cooling specimen,and tempered bainite with a polygonal structure containing large carbides and rare incomplete undecomposed M-A constituents was found in the tempered forced air cooling,static air cooling and furnace cooling specimens.The small effective grain size and fine carbides contributed to the good temperature impact toughness of the tempered water cooling specimens.

关 键 词：Alloy steel Quenching cooling rate Impact toughness Martensite-austenite(M-A)constituents Carbides 

分 类 号：TG1[金属学及工艺—金属学]