摘要
本文介绍一种只用高频产生等离子体的氮化方法(简称高频离子氮化法)。找出比较合适的氮-氢气体比例及合适气压、温度的氮化工艺参数。获得高的表面硬度(HV 1575左右)和较厚的氮化层(85μm)。初步分析了影响氮化层性质的一些因素。
18-8 austenite stainless steel was nitrogenized in a mixture of hydrogen andnitrogen gases plasmagenerated by RF with the power of 130W;Mixture gases ratio was1:4 at total pressures of 133Pa and 266Pa.After nitrogenizing for 7.2ks at temperatures of923,823 and 723K,the microstructure of the nitrided specimen was investigated by opticalmicroscopy,X-ray diffractometer and EPMA.The hardness of the nitride layer wasmeassured by a macrovickers,The thickness of nitride layer was about 35μm whennitrogenized at a total pressure of 133Pa at 823K.The maximum hardness of 1575HV wasobserved for the Specimen nitrogenized for 7.2ks at 723K.Only the γ′-phase was observedwith the surface relief caused by the transformaton twin when nitrogenized under ameassure of 266Pa and at 723K.The amount of the γ′-phase decreases with increase tem-perature.While the amount of CrN increases.In this connection hardness and the granularimage appear with the size of several μm on specimen surface.
出处
《材料科学进展》
EI
CAS
CSCD
1990年第1期32-37,共6页
关键词
不锈钢
高频
奥氏体不锈钢
austenite stainless steel
high frequency
plasma nitriding
