Mechanical Engineering Faculty Research

Title

Effect of Plastic Prestrain on High Cycle Fatigue of Ti–6Al–4V

Document Type

Article

Publication Date

Winter 2-2002

Abstract

The effect of initial plastic strain on the high cycle fatigue (HCF) lives of smooth cylindrical Ti–6Al–4V specimens is investigated. Specimens were monotonically, quasi-statically loaded under strain control in tension to produce plastic strains from 1% to 5% and under load control in compression to produce 9.5% plastic strain. A step-loading technique was then employed to establish the 106 or 107 cycle fatigue limit stress under load control conditions for stress ratios of R=0.1, 0.5 and 0.8 at frequencies of either f=50 or 400 Hz. Results are compared with baseline fatigue limit stresses for Ti–6Al–4V without prior plastic strain. Initial plastic prestrain in both tension and compression resulted in a small reduction in the fatigue limit at R=0.1, while a lesser reduction was exhibited at higher stress ratios in terms of maximum stress.

Publication Title

Mechanics of Materials

Volume

34

Issue

2

First Page

127

Last Page

134