Coating of Ti64 Bearings in Air by Using a Q-Sw Laser

Abstract:

The influence of surface oxidizing using a Q-sw laser on the wear loss of titanium-4Al-6V (Ti64) alloy during rolling contact fatigue is investigated. Titanium components are widely appreciated for their superb biocompatibility, high strength to weight ratio and corrosion resistance. Due to the above mentioned advantages titanium bearings are a popular choice in applications requiring high strength, light weight, and minimum maintenance (for example, aerospace and defence industries). In these rolling contact applications however issues such as fretting and wear related problems are a common occurrence as the tribological properties of titanium alloys are inferior to those of other metal alloys, such as steel. In an attempt to tackle this problem, a Q-sw laser was used in this work to coat Ti64 bearings with complex titanium oxide layers in a closed chamber without any protective gas. Non-coated and coated samples were tested under water by using a thrust-type rolling contact fatigue machine. The morphology and crystallographic texture of the layers were observed by laser confocal microscope, scanning electron microscope and X-ray diffraction. The wear loss of the coated samples was at least fifty-fold lower than that of the non-coated bearings and a 3-fold increase in the maximum load capacity compared with TiN layers was achieved.

• Periodical: Advanced Materials Research (Volumes 418-420)
• Pages: 393-397
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.418-420.393
• Online since: December 2011
• Authors: Justyna Rozwadowska, Katsuyuki Kida, Edson Costa Santos, Takashi Honda, Hitonobu Koike, Yuji Kashima, Ryo Matsumoto
• Keywords: Laser Coating in Air, Q-sw Laser, Rolling Contact Fatigue (RCF), Ti64

References

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DOI: 10.1016/j.surfcoat.2006.02.048

[4] J. Rozwadowska, E.C. Santos, T. Honda, H. Koike, K. Kida, Y, Kashima, K. Kanemasu, Improvement of the rolling contact fatigue of titanium by Q-sw laser nitriding, Processing and Fabrication of Advanced Materials XIX, New Zealand, January, (2011)

DOI: 10.4028/www.scientific.net/amm.83.191