摘要
采用X衍射和带能谱仪的扫描显微镜研究了17-4PH不锈钢QPQ(淬火-抛光-淬火)处理后渗层的显微组织和其中的C、N、O元素分布。结果表明:QPQ盐浴复合处理后可获得厚约60μm的渗层;表层为Fe3O4,亚表层为Fe2(N,C),最内层为CrN+αN扩展马氏体层。QPQ处理层的15～25μm范围内存在γ′-Fe4N,氧化物层和氮化物层的接触界面处会发生ξ-Fe2N1-x形核;氧浓度只在表面约3μm范围内具有最高值;N和C的浓度随深度增加在亚表面处先后出现峰值;除去表面的疏松氧化物层后,渗层的显微硬度随深度增加先升高后下降。
The micro-structure of the treated layer of 17-4PH stainless steel （SS） by the QPQ （Quench- Polish-Quench） complex salt bath heat-treatment was investigated, using X-ray diffractometer（XRD） for microstructure analysis and the scanning electronic microscopy （SEM） with EDS（energy dispersive spectrum） for the profile of carbon, nitrogen and oxygen of the treated layer. The results show that the QPQ heat-treated layer is approximately 60μm, of which the surface zone was the oxide Fe3O4; the subsurface zone is the compound ξ-Fe2（N,C） and the inner zone is the mixture of CrN and aN. The compound nitride 3,γ -FeaN exists between 15μm and 25μm. The interface between the oxide （magnetite） and the compound 3,＂ -Fe4N was supposed to be the place of the ξ-Fe2N（N,C）1-x nuclei. The oxygen concentration reveals the highest value at approximately 3μm from the surface, while the nitrogen and carbon concentration orderly reaches the high peak value at subsurface. After the oxidation layer was removed, the micro-hardness of the treated layer is observed to be first increasing and then declining with the depth increasing.
出处
《核动力工程》
EI
CAS
CSCD
北大核心
2007年第5期59-62,共4页
Nuclear Power Engineering
基金
核燃料及材料国家级重点实验室资助项目(W05-09)
