AN EXPERIMENTAL STUDY OF SUBSEQUENT YIELD SURFACES. CORNERS, NORMALITY, BAUSCHINGER AND ALLIED EFFECTS
Abstract
An initial yield and seven subsequent yield curves were determined from a sequence of loadings of the same thin-walled tubular specimen of 6061-T6 Al under tension and torsion, including reversed torsion. The yield curves were explored by piercing them very slightly at a number of points. Plastic strain-increment vectors for zigzag loading paths were determined also. Although initial yield curves and most subsequent yield curves resulting from appreciable plastic deformation in simple tension were smooth curves without regions of high local curvature, combined tension and torsion loading in the plastic range tended to develop a corner. Changes in the direction of the stress-increment vector did not produce consistent corresponding large changes in the direction of the plastic strain-increment vector. These observations indicated a blunt corner with a rounded rather than a pointed vertex. Convexity of all yield curves and normality of the plastic strain-increment vectors were verified, or at least not contradicted. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Jan 01, 1962
- Accession Number
- AD0275730
Entities
People
- P.k. Bertsch
- W.n. Findley
Organizations
- Brown University