基金The authors are grateful to the Department of Manufacturing Engineering, Annamalai University, Annamalainagar, Tamil Nadu, India for extending the facilities of Materials Testing Laboratory to carryout this investigation. The authors also wish to express their sincere thanks to Naval Research Board （NRB）, Ministry of Defence, New Delhi for the financial support to carryout this investigation through sponsored project N o.DNRD/05/4003/NRB/67. The authors also acknowledge the help rendered by Mr. Subbiah, Manager, LTM, Chennai, India to procure the base material.
