工业纯钛TA2交流电场增强粉末法铝碳氮共渗

Alternating current field enhanced pack aluminum-carbonitriding of commercial pure titanium TA2

对工业纯钛TA2在750℃进行交流电场增强粉末法铝碳氮共渗。采用金相显微观察、X射线衍射分析、显微硬度测试等分析试样渗层组织、相结构、渗层厚度以及显微硬度沿渗层深度方向的分布。结果表明,工业纯钛TA2经电流为2A的交流电场增强渗扩所得共渗层由TiN、Ti_(2)N以及少量AlTi_(3)构成,随电场电流逐步由2A增大至6A,渗层开始出现Ti_(3)AlN、C_(0.3)N_(0.7),Ti相,而TiN、Ti_(2)N消失,AlTi_(3)始终存在;TA2工业纯钛经同样渗剂、同样温度和同样时间常规渗扩后,渗层未检测到含铝相;交流电场对工业纯钛TA2粉末法铝碳氮共渗有显著促渗作用,促渗作用随电场电流的增大而增强;施加电流为6A的电场,能够获得厚度约40μm的渗层;交流电场还提高渗层硬度峰值及沿层深分布的整体硬度。

Alternating current field(ACF)enhanced pack aluminum-carbonitriding was carried out at 750℃for commercial pure titanium TA2.The microstructure,phase structure,thickness and microhardness distribution along the case depth of the treated specimens were analyzed by means of optical microscopy,X-ray diffraction and microhardness test.The results show that the case obtained with the help of the ACF with a current of 2 A consists of TiN,Ti,N and a small amount of AITi,.As the ACF current gradually increases from 2 A to 6 A,Ti_(3)AINand C_(0.3)N_(0.7)Ti are found in the surface layer,and the amount of TiN and Ti_(2)N disappear,while AITi,always exists.No aluminumcontaining phase is detected in the surface layer of TA2 treated by conventional pack aluminum-carbonitriding with the same agent,temperature and time used for the ACF enhanced treating.The ACF has a significant promoting effect on the pack aluminum-carbonitriding.The promoting effect increases with the increase of the ACF current.Applying an electric field with a current of 6 A can produces a case with a thickness about 40μm.The ACF also increases the case's peak hardness and overall hardness along the case's depth.