Effect Of Shot Peening On Fatigue Performance Of Two Titanium Alloys

Author:  H. Bae, B. Flinn, M. Ramulu, G. Weber and H. Diep
Source:  Conf Proc: ICSP-10 Tokyo, Japan 2008
Doc ID:  2008100
Year of Publication:  2008
Abstract:  
ABSTRACT The aerospace industry has taken interest in Ti 5Al-5Mo-5V-3Cr (Ti5553) for use in fatigue critical applications. To more fully understand the underlying fatigue mechanisms, Ti5553 was compared to the baseline alloy Ti 6Al-4V (Ti64) under cyclic loading conditions. This paper addresses the performance of as-machined and as-peened smooth round fatigue specimens of both alloys, including fatigue data, surface roughness, fractography and metallography. Surface topography of asmachined samples showed higher roughness values for Ti-5553 than Ti64, and the Ti5553 exhibited higher S-N plot scatter than Ti64. However, consistent fatigue behavior was demonstrated for the as-peened specimens. Fracture surfaces indicated standard fatigue and ductile failure modes. Shot peening process increased fatigue life of Ti5553 and Ti64 with increasing surface hardening and surface roughness.