Abstrait

Surface Modification of TIMETAL 834 by Excimer Pulse Laser

S. Mahanty, Gouthama

Ti alloys become very popular in various engineering fields due to its light weight, high strength and good corrosion resistance properties. Nevertheless, its application is limited in many areas like: tribology, high temperature oxidation and aggressive corrosion fields due to its poor surface properties. Therefore, the proper surface treatment is required to increase the usageof Ti alloys in such engineering field. In this present study, the surface modification of the Ti alloy is done by the excimer pulse laser. The various parameters used for the laser treatment are: pulse energy 5.4 Jcm-2, pulse repetition frequency 1 Hz, pulse width 20 ns, number of pulses 10 or 30, and atmosphere is ambient. The microstructural characterization is carried out by SEM, compositional analysis is done by the SEM/EDS and the tribological behavior is studied by the fretting wear test. It is observed that, the surface microstructure starts refining with increasing the number of pulse exposure.Initially,after 10 pulses, fine surface ripples prevailed, which became fairly broader later at 30 pulses. It is also found that in between 1 - 10 pulses, surface attained the compositional and microstructural homogeneity. A substantial decrease in average friction coefficient from 0.51 to 0.39 is observed for untreated to 30 pulses treated sample, indicating the significant enhancement in wear properties after laser processing.