SPS烧结W-10Ti合金的组织和性能

采用放电等离子烧结(SPS)技术制备了W-10Ti合金。通过扫描电镜和能谱分析了合金的微观组织,利用Den Broeder方法计算了合金的互扩散系数,测试了合金的密度和显微硬度,并与真空烧结的合金进行了对比。结果表明:与真空烧结相比,SPS烧结的合金组织均匀,富钛相少且细小,W在富钛相中的固溶度和Ti在富钨相中的固溶度都有所增加,且Ti在富钨相中的固溶度增加得更多。W-Ti合金的互扩散系数与W的摩尔浓度有一定的依赖关系,随着W摩尔浓度的升高呈先减小后增大趋势,SPS烧结的合金互扩散系数比真空烧结高出2个数量级。SPS法制备的W-Ti合金相对密度为96.1%,显微硬度HV0.05为5.21 GPa。

Microstructure and Properties of W-10Ti Alloy Sintered by SPS

W-10Ti alloys were prepared by the spark plasma sintering (SPS) technique. The microstructures of the prepared alloys were studied by scanning electron microscopy and EDS, and the interdiffusion coefficients were calculated by Den Broeder. In addition, the density and the micro-hardness were tested. Furthermore, vacuum sintered W-Ti alloy and SPSed W-10Ti alloy were compared. Results show that the microstructures of SPSed W-10Ti alloy are more uniform, the titanium-rich phase with reduced amount is smaller. Both the solid solubilities of Ti in W-rich phase and W in the Ti-rich phase increase, and the solubility of Ti in W-rich phase increases much more. The interdiffusion coefficients of W-Ti alloys have certain dependence on the W concentration; with the increase of W concentration, the coefficients decrease firstly and then increase. The interdiffusion coefficient of the SPSed alloy is two orders higher than that of the vacuum sintered alloy. The relative density of SPSed W-Ti alloy is 96.1%, and its micro-hardness HV0.05 is 5.21 GPa.