变电场辅助低温渗硼制备单相Fe_(2)B渗层  

Single⁃phase Fe_(2)B layer prepared by variable electric field assisted pack⁃boriding at low temperature

作　　者：丁红珍[1,2] 李航 邱万奇 Ding Hongzhen;Li Hang;Qiu Wanqi(School of Intelligent Manufacturing,Shunde Polytechnic,Shunde Guangdong 528300,China;School of Materials Science and Engineering,South China University of Technology,Guangzhou Guangdong 510640,China)

机构地区：[1]顺德职业技术学院智能制造学院,广东顺德528300 [2]华南理工大学材料科学与工程学院,广东广州510640

出　　处：《金属热处理》2024年第8期195-200,共6页Heat Treatment of Metals

基　　金：国家自然科学基金(51971095)。

摘　　要：以α-Al_(2)O_(3)为填充剂,2%活性炭为添加剂,对40CrNiMo钢进行恒压交流电场辅助渗硼,研究了渗硼电流的变化规律。通过调节交流电场电压得到稳定的低温渗硼温度,在40CrNiMo钢表面制备渗硼层,利用X射线衍射(XRD)、扫描电镜(SEM)和显微硬度计对渗硼层进行了表征。结果表明,因活性炭吸附在α-Al_(2)O_(3)粉末表面形成稳定的导电结构,使电场辅助渗硼不同阶段的渗硼电流相对稳定,从而可得到相对稳定的渗硼温度。调节电场电压将实际渗硼温度控制在较低温度(650、680、700℃),可在40CrNiMo钢表面制备致密单相Fe_(2)B渗硼层。经SEM观察渗硼层厚度≥13μm,且渗层表层硬度均较高,即使在650℃渗硼,硬度也可达约1200 HV0.05。Usingα⁃Al_(2)O_(3) powder as boriding filler and 2%activated carbon as additive,the variation of boriding current was investigated under a constant AC electric field assisted pack⁃boriding carried out on 40CrNiMo steel.By adjusting the AC electric field voltage to obtain stable low temperature boriding temperature,a borided layer was prepared on the surface of 40CrNiMo steel and characterized by X⁃ray diffraction(XRD),scanning electron microscopy(SEM)and microhardness tester.The results show that a stable conductor is created as a result of activated carbon adhering to the Al_(2)O_(3) powder's surface,which stabilizes the boriding current at different stages of the electric field assisted pack⁃boriding,resulting in a relatively stable boriding temperature.A dense single⁃phase Fe_(2)B borided layer on the surface of 40CrNiMo steel can be prepared by adjusting the electric field voltage to control the actual boriding temperature at a lower temperature(650,680,700℃).The SEM observation shows that the thickness of the borided layer is≥13μm.The surface hardness of the borided layer is relatively high and can reach about 1200 HV0.05 even at 650℃.

关 键 词：变电场 低温渗硼 硬度 Fe_(2)B 

分 类 号：TG156.8[金属学及工艺—热处理]