Influence of Superplastic Forming on Reduction of Yield Strength Property for Ti-6Al-4V Fine Grain Sheet and Ti-6Al-4V Standard

Abstract:

The SPF experiments were conducted on two sheet materials: Ti-6Al-4V Fine Grain Sheet (Ti-64 FGS) and Ti-6Al-4V Standard (Ti-64 STD) to investigate the influence of SPF conditions on the reduction of yield strength (YS) and change in microstructure for those two products. Results show that a) Ti-64 FGS has better formability at high testing strain rate than Ti-64 STD, b) initial YS values of Ti-64 FGS is 10% higher than Ti-64 STD, c) reduction of YS in Ti-64 FGS is 15-27%, which is much higher than 4-9% YS reduction for Ti-64 STD, d) the most influential factor on YS reduction is the forming temperature for Ti-64 FGS, but is the strain rate for Ti-64 STD, and e) microstructure pictures of initial Ti-64 FGS before forming is finer and more isotropic than Ti-64 STD, but Ti64 FGS shows more grain growth after SPF, which results in greater drop of yield strength.

• Periodical: Materials Science Forum (Volumes 838-839)
• Pages: 171-176
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.838-839.171
• Online since: January 2016
• Authors: P. Sartkulvanich, Don Li, Ernest Crist, K.O. Yu
• Keywords: Fine Grain Sheet, Finite Element, SPF, Superplastic Forming, Titanium Sheet

References

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