Stretch Forming and Fracture of Strongly Textured Ti Alloy Sheet
Abstract
The influence of plastic anisotropy and R-value on the stretch forming and fracture behavior of strongly textured Ti-6Al-4V and Ti-5Al-2.5Sn sheet has been examined utilizing sheet specimens with a wide range of R-values but with similar work hardening and strain rate sensitivity characteristics. The results indicate that a high R-value and difficult through-thickness slip enhance the forming limit as well as fracture strains when the minor strain in the plane of the sheet is negative, this effect being most pronounced at uniaxial tension. At plane strain, the R-value has little or no influence on the limit or fracture strain. A direct determination of the effect of R-value on the biaxial strecth forming characteristics of Ti-6-4 sheet is precluded by the intervention of fracture prior to localized necking when the minor strain is positive. The influence of plastic anisotrophy on both the localized necking and the fracture behavior can be generally understood in terms of difficulty of attaining critical thickness strains as through-thickness slip becomes more difficult.
Document Details
- Document Type
- Technical Report
- Publication Date
- Mar 01, 1982
- Accession Number
- ADA115385
Entities
People
- Donald A. Koss
- K. S. Chan
Organizations
- Michigan Technological University