施加直流电场的快速粉末渗铬工艺  

Rapid powder chromizing technology assisted by direct current field

作　　者：周正华[1,2] 谢飞[1,2] 潘献波[1,2] 王燕[1,2] 胡静[1,2] 

机构地区：[1]常州大学材料科学与工程学院,江苏常州213164 [2]常州市先进金属材料高技术研究重点实验室,江苏常州213164

出　　处：《材料热处理学报》2011年第2期130-133,共4页Transactions of Materials and Heat Treatment

基　　金：江苏省高校自然科学基金(06KJB430021;07KJD430037);常州大学大学生科技创新基金

摘　　要：通过在渗扩介质与被渗样品间施加合适参数的直流电场予以实现快速粉末渗铬。选择碳素钢(45钢和20钢)为研究对象,分析了直流电场对渗铬层显微组织、渗层厚度及温度场的影响,分析了施加直流电场条件下温度对渗层厚度的影响,并研究了施加直流电场快速渗铬获得的渗层的高温抗氧化性。结果表明,直流电场可降低粉末渗铬温度,显著增加渗速;可将常规粉末渗铬温度950～1100℃降低到850℃以下;加热温度为700～850℃时,通过施加合适的直流电场,渗铬层厚度可达到60μm以上。直流电场不仅对试样有加热作用,而且在两极间形成温度差。快速渗铬新工艺获得的渗铬试样在700℃以下具有良好的抗氧化性能。A low-temperature powder chromizing technology was developed by applying direct current field（DCF） between the treated sample and the powder agents.The cross-sectional microstructure was studied,and the chromizing coating thickness and high temperature oxidation resistance were investigated.The results show that DCF can significantly reduce the treating temperature and heating duration comparing with the conventional powder chromizing processes,thus providing a practical approach with great energy and time saving.When the treating temperature was in the range of 700 ℃-850 ℃,the chromizing coatings with thickness larger than 60 μm were produced by applying appropriate intensity of DCF.It was also found that DCF could not only heat the sample,but also form temperature gradient between the two electrodes.The chromizing coating rapidly formed at lower temperature exhibits good oxidation resistance below 700 ℃.

关 键 词：粉末渗铬 直流电场 抗氧化 

分 类 号：TG156.8[金属学及工艺—热处理]