PLASMA CHROMIZING TECHNOLOGY ON TiAl ALLOY SURFACE

Chromizing treatment of TiAl intermetallic is conducted by double glow plasma metallic cementation technology and alloyed layer was formed on the surface. Effects of temperature,gas pressure,source electrode voltage and cathode voltage on composition,thickness and microstructure of the alloyed layer are studied systematically．According to the experiments,after 2 hours chromising at 1 050 ℃,the thickness of alloyed layer reaches 60 μm,the composition of the layer changes gradually with the depth,and the surface microhardness increased simultaneously.