直流电场对粉末法渗铝的影响  

Influence of direct current field on powder aluminizing

作　　者：周正华[1] 谢飞[1] 胡浩波[1] 胡静[1] 

机构地区：[1]江苏工业学院材料科学与工程学院,江苏常州213164

出　　处：《材料热处理学报》2008年第6期154-157,共4页Transactions of Materials and Heat Treatment

基　　金：江苏省高校自然科学基金(06KJB430021)

摘　　要：新粉末渗铝技术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。分析了渗铝层显微组织及渗层厚度,测量了渗层硬度沿层深的分布及直流电场对温度场的影响,并进行了抗氧化性研究。研究结果表明:直流电场可降低外热温度,显著增加渗速;可将常规粉末渗铝温度900℃以上降低到700℃～750℃;外热温度为700℃～750℃时,通过施加合适的直流电场,渗铝层厚度可达到或超过180μm。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。新工艺处理的渗铝试样在850℃以下具有良好的抗氧化性能。A low-temperature powder aluminizing technology was developed by applying direct current field （DCF） between the treated sample and the powder agents. The microstructures of the aluminized layer was studied. The thickness and micro-hardness distribution of the aluminized layer was measured and its high temperature oxidation resistance was investigated. The results show that DCF can significantly reduce the treating temperature and heating duration compared with the conventional powder aluminizing process, providing a practical approach with great energy and time saving. When the treating temperature is 700℃ - 750℃ , the aluminizing layer with thickness no less than 180μm is produced by applying appropriate intensity of DCF. It is also found that DCF can not only heat the sample, but also form temperature gradient between the two electrodes .The aluminizing layer rapidly formed at lower temperature exhibits good oxidation resistance below 850℃ .

关 键 词：粉末渗铝 直流电场 抗氧化 

分 类 号：TG156.8[金属学及工艺—热处理]