A novel duplex low-temperature chromizing process at 500 degrees C

作者：Cao, Huiliang; Wu, Cuilan; Liu, Jiangwen; Luo, Chengping^*; Zou, Ganfeng

来源：Journal of Materials Science & Technology, 2007, 23(6): 823-827.

• chromizing
• plasma nitriding
• thermoreactive deposition and diffusion (TRD)
• CrN

An optimized low-temperature chromizing process at 500 degrees C was realized on a plain medium-carbon steel with 0.45 wt pct carbon via a duplex chromizing process which consists of a precursor plasma nitriding, and a followed salt bath thermoreactive deposition and diffusion (TRD) chromizing process. CrN layer with a thin diffusion layer underneath was formed. The duplex chromizing process was studied by optical microscopy (OM), scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDS), X-ray diffraction (XRD), and transmission electron microscopy (TEM). It was found that the chromizing speed at 500 degrees C was successfully enhanced by adding more Cr-Fe powders into the salt bath, and the CrN layer formed at the cost of the prior nitride compound layer. A CrN layer with average 8.1 mu m in thickness and 1382 HV0.01 in microhardness was formed on the substrate by duplex chromizing at 500 degrees C for 24 h. Further more, the CrN layer consisted of nanocrystalline CrN grains.

• 出版日期2007-11
• 单位湖南大学; 华南理工大学