摘要
低温等离子体氮化技术能显著提高奥氏体不锈钢的机械性能,氮化过程中气压对强化效果的影响尤为显著。本文实验研究了氮气流量对低温等离子体氮化奥氏体不锈钢相组成、形貌、元素分布、硬度及耐磨性的影响。结果表明:低温等离子体氮化处理能够在不锈钢表面形成具有强化作用的氮化层,该氮化层由扩展奥氏体γN相和少量CrN和Fe4N组成。随着氮气流量增加,扩展奥氏体晶格常数从0.408 nm下降至0.398 nm,氮化物逐渐消失;氮化层厚度减小;同时硬度值与耐磨性降低。其中,氮气流量为100 mL/min的氮化试样磨损量最小,仅为基体的0.4%。
Low temperature plasma nitriding technology can markedly improve the mechanical properties of austenitic stainless steel,and especially the effect of gas phase pressure on the strengthening effect in nitriding process is more significant.In the present work,influences of nitrogen flowrate on phase composition,morphology,element distribution,hardness and wear resistance of the austenitic stainless steel treated by using low temperature plasma nitriding technology were investigated experimentally.The experimental results showed that,through low temperature plasma nitriding,an enhanced nitriding layer was formed on the surface of the stainless steel,which consisted primarily of the expanded austeniteγN phase and a trace of CrN and Fe4N mixture.As nitrogen flowrate increased,the lattice constant of the expanded austenite decreased from 0.408 nm to 0.398 nm;the nitrides gradually diminished and thus the thickness of the nitriding layer decreased;and,accordingly,the hardness and the wear resistance of the stainless steel reduced.For instance,for nitrogen flowrate of 100 mL/min,the wear rate of the nitrided sample was only 0.4%of that of the substrate.
作者
滕越
郭媛媛
徐晗升
朱紫薇
刘波
黄振
杨永杰
刘磊
TENG Yue;GUO Yuanyuan;XU Hansheng;ZHU Ziwei;LIU Bo;HUANG Zhen;YANG Yongjie;LIU Lei(School of Materials and Metallurgy,University of Science and Technology Liaoning,Anshan 114051,China;School of Science,University of Science and Technology Liaoning,Anshan 114051,China)
出处
《辽宁科技大学学报》
CAS
2018年第6期433-438,共6页
Journal of University of Science and Technology Liaoning
基金
国家自然科学基金青年基金(51502126
11805089)
辽宁省自然科学基金(20180550802)
辽宁科技大学省级重点实验中心开放课题(USTLKFSY201705)
辽宁科技大学大学生创新创业项目(201810146145
201710146216)
校青年基金(2018QN12)
关键词
奥氏体不锈钢316L
低温等离子体辅助氮化
扩展奥氏体
微观结构
机械性能
316L austenitic stainless steel
Low temperature plasma assisted nitriding
Expanded austenite
Micro-structure
Mechanical property
