Surface modification of pure Ti with TiB₂/Si₃N₄ reinforced coating

Abstract

In this study, Al–Ti–Co was first used to improve the surface performance of pure Ti. The synthesis of hard composite coating on pure Ti by laser cladding of Al–Ti–Co+TiB₂/Si₃N₄ preplaced powders was investigated in detail. The SEM result indicated that a composite coating with metallurgical joint to the substrate was formed, and the coating can also have major dilution from the substrate. X-ray diffraction result indicated that this composite coating mainly consisted of Ti₃Al, TiB₂, TiB, TiN, Ti₅Si₃ and Co–Ti intermetallics. Compared with pure Ti, the improvement of the microhardness and wear resistance was observed for this composite coating.

Keywords:

• Surface modification
• Laser cladding
• Wear

This work was financially supported through the Science Foundation for Excellent Young Scientist of Shandong Province, China (grant no. BS2011CL027). And Professor T. Zhai of University of Kentucky (USA) is gratefully acknowledged for the help of testing and microstructural discussions.