Highly efficient gas nitriding using atmosphere control and computational process simulation
To optimizenitrided layers in response to various requests from usersmore efficiently and effectively, practicable gas nitridingprocesswas developed.In particular, nitriding-process parameters used with this method are controlled by predicting the compound layercomposition and thickness of the nitride layer by computer simulation based on the CALPHAD method.The predictable property of the nitrided layer of low-alloy steels in practical use (JIS SCM435 and DIN 31CrMoV9 steels) includes compound-layer composition and hardness of the nitrogen-diffusion layer.As an example of a highly-efficient gas nitriding, a two-stage gas-nitriding process, whichconsists of γ-phase forming (first stage) and γ-phase dissolution under an isothermal nitrogen gas-only atmosphere (second stage), is proposed.This nitridingprocess is efficiently designed by the computer-simulation method and eliminatesthe need for a compound layer on thenitrided layer of a low-alloy steel but still produces a high-hardness diffusion layer.
gas nitriding nitrogen atmospherecontrol nitrogen potential compound layer γ-phase ε-phase nitride low-alloy steel simulation
Youichi Watanabe
3-13-10, Tamachi Kanagawa-ku , Kawasaki-shi , Kanagawa , 210-0822 Japan Parker Netsushori Kogyo Co., Ltd.
国际会议
北京
英文
67-76
2014-10-11（万方平台首次上网日期，不代表论文的发表时间）