空气预氧化与盐浴预氧化对盐浴渗氮催渗效果的对比  

Comparision of Enhancement Effect Between Air Pre-oxidation and Salt Bath Pre-oxidation on Salt Bath Nitriding

作　　者：戴明阳[1] 魏坤霞[1,2] 陈尧[1] 宋仁国[1,2] 孙斐[3] 胡静[1,2] DAI Ming-yang WEI Kun-xia CHEN Yaol, SONG Ren-guo SUN Fei HU Jing(Jiangsu Key Laboratory of Materials Surface Science and Technology Jiangsu Collaborative Innovation Center of Photovolatic Science and Engineering, Changzhou University, Changzhou 213164, Jiangsu Department of Mechanical En- gineering, Changzhou Institute of Light Industry Technology, Changzhou 213164, Jiangsu)

机构地区：[1]常州大学江苏省表面科学与技术重点实验室,江苏常州213164 [2]常州大学江苏省光伏科学与工程协同创新中心,江苏常州213164 [3]常州轻工职业技术学院机械工程系,江苏常州213164

出　　处：《中国表面工程》2016年第6期38-43,共6页China Surface Engineering

基　　金：江苏省研究生创新基金(SCZ100431322);江苏省科技成果转化项目(BA2013078)

摘　　要：以45钢为试验材料,采用空气炉和盐浴炉两种方式进行预氧化,随后进行相同工艺的盐浴渗氮处理。对比分析两种预氧化方式对盐浴渗氮效率和组织性能的影响。利用光学显微镜、X射线衍射仪、显微硬度计、电化学工作站和扫描电镜对样品的显微组织、物相、硬度、耐蚀性和表面形貌进行了测试和分析。预氧化试样表层物相分析发现,盐浴预氧化和空气预氧化处理45钢表面均形成含有Fe_3O_4的氧化膜,但是随着保温时间延长盐浴预氧化处理试样表面氧化膜中的Fe_3O_4含量增速更快、含量更高,且具有更大的比表面积,在随后的渗氮处理中容易被还原。盐浴预氧化(350℃×45 min)后进行盐浴渗氮(560℃×120 min),化合物层厚度达到了20.8μm,显著地提高盐浴渗氮效率,是相同工艺参数空气预氧化后盐浴渗氮所获得化合物层厚的1.6倍。同时能改善渗层组织性能,耐腐蚀性能提高。45 carbon steel was selected as the testing material and rapid salt bath pre-oxidation nitriding was compared with normal air pre-oxidation nitriding. Optical microscopy （OM）, X-ray diffraction （XRD）, micro-hardness testing, electrochemical workstation and scanning electron microscope （SEM） were employed to analyze the microstructure, phase, micro-hardness, corrosion resistance and surface morphology. The results show that Fe3O4 phase is formed on the sample surface after different pre-oxidation process. However, the relative amount of Fe3O4 treated by salt bath pre-oxidation is higher than that treated by normal air pre-oxidation. Meanwhile, the sample treated by salt bath pre-oxidation has higher specific surface area than that treated by air pre-oxidation, which is beneficial to be reduced. The maximum compound layer with a thickness of 20.8 μm is obtained after nitriding at 560℃ for 120 min under the optimum pre-oxidation condition of 350℃ and 45 min, which is more than 1.6 times thicker than that by normal air pre-oxidation, and the corrosion resistance treated by salt bath pre-oxidation is further enhanced.

关 键 词：预氧化 盐浴渗氮 显微结构 硬度 耐蚀性 

分 类 号：TG156.8[金属学及工艺—热处理] TG174.451[金属学及工艺—金属学]