摘要
为了提高高镍铬含量不锈钢的抗渗碳性,探索了奥氏体不锈钢表面的渗硅效果。通过扩散处理,在304奥氏体不锈钢表面获得了结构致密的渗硅层。应用SEM电镜和EDS能谱分析、显微硬度测定等方法观察了渗硅层的微观结构及其性能。结果表明,渗硅层厚度达50μm以上,为典型的柱状晶结构;渗层晶粒中由里到外的硅浓度分布区间为12.24%～20.93%;相应的微观组织的细密程度由表及里呈梯度分布,与基体结合处呈纳米晶结构;显微硬度由里到外在406～477HV1N。缺口断裂法试验结果表明,渗硅层与钢基体结合十分良好。
Fine and compact siliconized layer was prepared on the surface of AISI-304 stainless steel via pack cementation siliconiz-ing of mixed Si-Fe alloy powder with 70% Si (mass fraction) in the presence of SiO2 as a loosening agent. The microstructure of the siliconized layer was analyzed by means of scanning electron microscopy and X - ray energy dispersive spectrometry. Besides, the microhardness of the siliconized layer was measured, and its adhesion to substrate was evaluated by conducting notched break-ing test. Results indicate that the siliconized layer has a thickness of over 50 μm and shows typical columnar crystal structure. The Si concentration of the siliconized layer was ranged within 12.24% ～20. 93% from the inner zone to the surface, and the corresponding microstructure assumed gradient distribution from the surface to the inner zone, while nanocrystal structure appeard at the interface. At the same time, the siliconized layer had a micro-hardness of 406 ～ 477 HV1N from the inner zone to the surface, and was well bonded with the steel substrate.
出处
《材料保护》
CAS
CSCD
北大核心
2010年第3期14-16,共3页
Materials Protection
关键词
粉末渗硅
奥氏体不锈钢
梯度材料
微观组织
纳米表面
结合强度
pack cementation siliconized layer
austenite stainless steel
gradient materials
microstructure
nanocrystal surface
adhesion strength
