频率对交流电场增强45钢低温粉末法硼铝共渗的影响  

Effect of frequency on alternating current field enhanced pack boron-aluminizing on 45 steel at low temperature

作　　者：杨彦飞 谢飞 Yang Yanfei;Xie Fei(School of Materials Science and Engineering,Changzhou University,Changzhou Jiangsu 213164 ,China;Key Laboratory of Materials Surface Engineering of Jiangsu Province,Changzhou University,Changzhou Jiangsu 213164,China)

机构地区：[1]常州大学材料科学与工程学院,江苏常州213164 [2]常州大学江苏省材料表面技术重点实验室,江苏常州213164

出　　处：《金属热处理》2019年第5期106-110,共5页Heat Treatment of Metals

基　　金：国家自然科学基金(51171032)

摘　　要：通过一对相互平行的平板电极,对45钢试样和渗剂施加交流电场,研究电场频率对750℃以渗硼为主的粉末法硼铝共渗(以下简称硼铝共渗)的影响。以X射线衍射、光学显微观察与显微硬度测试等手段分析共渗层。结果表明:不同频率交流电场均对45钢硼铝共渗进程有显著促进作用,共渗层均由(Fe_(1-x)Al_x) B和(Fe_(1-x)Al_x)2B两相组成;电场电流恒为2 A时,电场频率从50 Hz增大至500 Hz,共渗层厚度先减小,在100 Hz时,共渗层厚度和其中的(Fe_(1-x)Al_x) B相厚度达最小,随后二者又逐渐增加;交流电场除对B、Al原子和含B、Al的活性基团在渗扩件表面的吸附有一定程度的负面作用外,对硼铝共渗过程中其他过程均为正面作用。An alternating current field( ACF) with adjustable frequencies was applied to pack media and 45 steel specimens with a pair of electrodes paralleling with each other during pack boron-aluminizing( PBA) at 750 ℃.The influence of the ACF frequency on PBA was studied,in which,boriding was dominantly investigated.The boron-aluminized layers were investigated with X-ray diffraction,optical microscopic observation and micro-hardness test.The results show that the ACF with different frequency can enhance the PBA.The obtained boron-aluminized layers are all composed of( Fe1-xAlx) B and( Fe1-xAlx)2 B.When the ACF current is kept at 2 A,the increase of the ACF frequency from 50 Hz to 500 Hz can make the boron-aluminized layer total thickness and the( Fe1-xAlx) B zone thickness decrease first and then increase.The minimum thickness is obtained at 100 Hz.It is proposed that the ACF has positive effects to PBA processes but a negative effect,to some extent,to the adsorption of active atoms of aluminium and boron and active species containing aluminium and/or boron on specimen surface.

关 键 词：粉末法硼铝共渗 交流电场 频率 显微组织 

分 类 号：TG156.8[金属学及工艺—热处理]