摘要
通过直接向离子渗氮炉通入空气的方法,首次研究预氧化对42Cr Mo钢离子渗氮的作用。采用金相显微镜、显微硬度计、XRD研究了渗氮层厚度和渗氮层物相。结果表明,预氧化对离子渗氮具有明显的催渗作用,在300℃预氧化30 min后进行离子渗氮(500℃×4 h),化合物层厚度达到15μm,是不经预氧化处理的传统离子渗氮化合物层厚度的2倍以上;有效扩散层厚度达到最大值570μm,明显高于传统离子渗氮的有效扩散层厚度。
The effects of pre-oxidation on plasma nitriding for 42 Cr Mo steel were investigated primarily by imputing air directly into the furnace. The nitride layer and phase microstructure were investigated by OM, microhardness tester and XRD.The results show that pre-oxidation has significant catalysis effect on plasma nitriding, and the maximum compound layer thickness of 15 μm is obtained after nitriding at 500 ℃ for 4 h under the optimum pre-oxidation（PO） condition of 300 ℃ and30 min, which is more than twice thicker than that without pre-oxidation; and the maximum effective diffusion layer of570 μm is obtained, which is much thicker than that without pre-oxidation. XRD results show that the oxide formed during oxidizing can be transformed to nitride after nitriding.
出处
《热加工工艺》
CSCD
北大核心
2014年第22期177-179,183,共4页
Hot Working Technology
基金
常州市科技支撑项目(CE20110098)
