TC4钛合金碳氮复合渗层的组织结构与性能

Microstructure and properties of the C-N compound layer prepared on TC4 titanium alloy surface

利用真空脉冲碳氮复合渗技术在TC4钛合金表面制备了梯度强化层。采用XRD和SEM对复合渗层组织结构进行了表征,并对其硬度分布、耐磨性和耐蚀性进行了分析。结果表明,经过真空脉冲碳氮复合渗处理后的TC4钛合金表层由TiC、TiN和C_(0.7)N_(0.3)Ti相组成。其中先渗碳后渗氮工艺所获得的合金渗层最厚,其磨损率达到5.370×10^(-8)cm^3·min^(-1)·N^(-1),只有原样的1/36,腐蚀速率从原样的13.5 mm/a减小到0.421 mm/a,综合性能最优。

The strengthening gradient layer was prepared on TC4 titanium alloy surface by vacuum pulse carburizing and nitriding compound infiltration technology. Phase and microstructure of the C-N compound layer were investigated by means of XRD and SEM. The hardness gradient, wear resistance and corrosion resistance of the layer were also studied. The results show that the C-N compound layer is composed of TiC, TiN and C0.7N0.3Ti phases. The maxium thickness of the C-N compound layer prepared by firstly carburizing and then nitriding is obtained, and its wear rate is 5. 370 × 10^-8 cm^3·min^-1·N^-1 , only 1/36 that of the TC4 titanium alloy matrix, the corrosion rate reduces from 13.5 mm/a of the TC4 titanium alloy matrix to 0. 421 mm/a for the alloy with C-N compound layer.