Comprehensive analysis of pulsed plasma nitriding preconditions on the fatigue behavior of AISI 304 austenitic stainless steel  

作　　者：Okan Unal Erfan Maleki Remzi Varol 

机构地区：[1]Mechanical Engineering Department,Karabuk University,Karabuk 78050,Turkey [2]Modern Surface Engineering Laboratory(MSELAB),Karabuk University,Karabuk 78050,Turkey [3]Mechanical Engineering Department,Sharif University of Technology-International Campus,Kish Island 79417-76655,Iran [4]Mechanical Engineering Department,Suleyman Demirel University,Isparta 32200,Turkey

出　　处：《International Journal of Minerals,Metallurgy and Materials》2021年第4期657-664,共8页矿物冶金与材料学报（英文版）

基　　金：the Scientific and Technological Research Council of Turkey(TUBITAK)for the support of this study(Grant No:215M134)。

摘　　要：This study aims to draw an exact boundary for microstructural and mechanical behaviors in terms of pulsed plasma nitriding conditions.The pulsed plasma nitriding treatment was applied to AISI 304 austenitic stainless steel at different temperatures and durations.Results reveal that nitriding depth increased as process temperature and duration increase.The nitriding depth remarkably increased at 475℃for 8 h and at 550℃for 4 h.An austenite structure was transformed into a metastable nitrogen-oversaturated body-centered tetragonal expanded austenite(S-phase)during low-temperature plasma nitriding.The S-phase was converted to CrN precipitation at 475℃for 8 h and at 550℃for 4 h.Surface hardness and fatigue limit increased through plasma nitriding regardless of process conditions.The best surface hardness and fatigue limit were obtained at 550℃for 4 h because of the occurrence of CrN precipitation.

关 键 词：pulsed plasma nitriding S-PHASE FATIGUE nitrided layer 

分 类 号：TG156.82[金属学及工艺—热处理] TG142.71[金属学及工艺—金属学]