【摘要】 目的研究等离子体刻蚀工艺对高碳马氏体不锈钢表面渗铬层组织和结合强度的影响。方法首先利用微波等离子体化学气相沉积方法对8Cr17马氏体不锈钢表面进行四种不同工艺参数的刻蚀处理,然后利用双层辉光等离子体表面渗铬技术在刻蚀处理后的8Cr17不锈钢表面制备铬合金层。用扫描电子显微镜、激光共聚焦、辉光放电光谱仪和X射线衍射仪分别表征刻蚀表面形貌和渗铬层组织,用划痕仪测试渗铬层与基体的结合强度。结果氢和氢+氩等离子体刻蚀后,8Cr17不锈钢基体表面粗糙度增加,且含碳量减少。渗铬层由表面富Cr层、Cr_xC_y扩散层、基体组成,其物相主要包括Cr、Cr₂₃C₆、Cr₇C₃。表面经氢气刻蚀1 h和2 h后,形成的渗铬层厚度分别为7、7.5μm,氢气+氩气刻蚀1 h和2 h后,渗铬层厚度分别为8.1、9μm,其中氢气+氩气刻蚀1 h的基材表面渗铬层较致密,与基体结合牢固。结论等离子体刻蚀预处理可通过改变8Cr17钢表面的组织形貌,降低表面含碳量,增加扩散层厚度,提高渗层与基体的结合强度。更多还原

【Abstract】 The work aims to study the effect of plasma etching process on the structure and bonding strength of chromizing layer on the surface of 8Cr17 high carbon martensitic stainless steel. 8Cr17 steel was firstly etched with four different process parameters by microwave plasma chemical vapor deposition method, and then the double glow plasma surface alloying was applied to prepare chromizing alloy layer on the etched 8Cr17 surface. Scanning electron microscopy, laser scanning confocal microscopy, glow discharge optical emission spectrometer and X-ray diffraction were used to characterize the morphology of etched surface and microstructure of chromizing layer. The bond strength between chromizing layer and substrate was measured by a scratch tester. The surface roughness increased, but the surface carbon was consumed after hydrogen and hydrogen + argonetching. The chromizing layer with Cr, Cr₂₃C₆ and Cr₇C₃ was composed of surface Cr rich layer/CrxCy diffusion layer/substrate. The thickness of the chromizing layer formed on the pretreated surface after hydrogen etching for 1 h and 2 h was 7.5 μm and 7.5 μm, and hydrogen + argon etching for 1 h and 2 h was 8.1 μm and 9 μm, respectively, and the chromizing layer after hydrogen + argon etching for 1 h was dense and had a strong adherence to substrate. The etching process obviously results in an increase of the diffusion thickness as well as bonding strength between chromizing alloy layer and substrate.更多还原