Tribological Performance of TiAl Based Alloy Treated with Plasma Surface Chromizing Process

TiAl-Cr alloy was prepared on surface of TiAl based alloy by plasma surface alloying technique. The wear resistance of the surface alloy was examined under various wear condition. During the room temperature ball-on-dic sliding test, the TiAl-Cr surface alloy showed reduced friction and improved wear resistance. For the 500 degrees C sliding and room temperature fretting tests, the friction coefficient of TiAl-Cr surface alloy was a little higher than that of TiAl-based alloy, but the wear volume showed significant reducing, the wear resistance was improved obviously. The addition of chromium increases the strength and hardness of the TiAl-based alloy, and therefore the load bearing and anti-adhesion capacity of the surface were also enhanced, these were the main mechanisms for the improvement of wear resistance.