Effect of Beta Flecks on Low-Cycle Fatigue Properties of Ti-i OV-2Fe-3A1

摘要

The effect of beta flecks on low-cycle fatigue (LCF) properties was investigated at room temperature for a high-temperature (#alpha# + #beta#)-processed and also a #beta#-processed Ti-10V-2Fe-3A1 alloy. For both the (#alpha# + #beta#)processed and the #beta#-processed material, beta flecks had a significant influence on LCF and tensile properties. The materials with beta flecks showed a loss in LCF life and ductility. Larger beta flecks resulted in lower LCF life and ductility. It seemed that fl4orged material contained much smaller beta flecks but had a similar detrimental effect on LCF properties as the (#alpha# + #beta#)-processed one. Based on the diffusion calculation, it could be concluded that chemical composition inhomogenieties could not be reduced by using beta forging in the 820 deg C #beta# region. Extensive light microscopy and scanning electron microscopy (SEM) observations showed that beta flecks were susceptive to crack nucleation and propagation.