采用间歇式真空氮化技术对TA2钛合金进行渗氮处理。探究氮氩混合比对合金氮化层结构和性能的影响规律。结果表明:表面渗氮层主要由TiN和TiN0.3相组成,氮氩比越低其有效硬化层越厚,但会降低有效活性N原子的相对含量,不利于渗层的致密性。适当的氮氩混合比能在TA2表面形成氮化物,N原子有效地向纵深扩散,氮化物层与扩散层结合紧密,过渡良好,硬度梯度平缓;腐蚀电位随着氮氩比的增加呈现逐渐上升趋势,从氮氩比为1∶5时的-0.622V提升到氮氩比为5∶1时的-0.549V,腐蚀电流和腐蚀速率则呈现出逐渐降低的趋势。
The TA2 industrial pure titanium was treated by the intermittent vacuum nitriding method.The influence of nitrogen argon ratio on the microstructures and properties of nitrided layer was investigated.The results showed that TiN and TiN0.3 were the main phase of the substrate surface.With the decrease of nitrogen-argon ratio,the effective hardening layer depth increased,but the compactness decreased because of the rarefied nitrogen.The nitride surface and diffusion depth can be formed under an appropriate nitrogen-argon ratio.And under this conditions,the nitrided layer and diffusion layer combined closely with gentle hardness gradient.The corrosion potential showed an upward trend which increased from-0.622Vto-0.549 Vwith the nitrogen-argon ratio from 1∶5to 5∶1.However,the corrosion current and corrosion rate exhibited versa trends.