Effects of Nd:YAG Laser Surface Treatment on Tribological Properties of Cold-Sprayed Ti-6Al-4V Coatings Tested against 100Cr6 Steel under Dry Condition

Abstract

The surfaces of cold-sprayed Ti-6Al-4V (Ti64) coatings were laser irradiated with different laser powers of 50–200 W to study the effects of Nd:YAG laser surface treatment on their tribological properties. The hardness of the laser-treated Ti64 coatings became higher with higher laser power due to the more rapid cooling caused by a larger temperature difference between the coating temperature and room temperature. The wear of the laser-treated Ti64 coatings tested against 6-mm 100Cr6 steel balls under dry condition at room temperature decreased with increased laser power as a result of their increased surface wear resistance associated with their increased surface hardness. It could be concluded that the laser surface treatment of the cold-sprayed Ti64 coatings improved their surface wear resistance compared to that of the untreated Ti64 coatings.

Keywords:

• Cold spray
• laser surface melting
• laser power
• Ti-6Al-4V
• hardness
• wear

Acknowledgements

The authors are grateful to the project team members from Rolls-Royce, Singapore, Anna Tai and Nicholas Weeks, for their contributions to this work.

Additional information

Funding

The authors are grateful for financial support from the National Research Foundation (NRF), Rolls-Royce (RR), and Nanyang Technological University (NTU), Singapore (NRF-RR-NTU research grant number of M-RT3.1). W. Sun is grateful to NTU for his Ph.D. scholarship.