# Accession Number:

## AD0726443

# Title:

## Calculations on the Effect of the Stress State on the Fracture Ductility of Solids.

# Descriptive Note:

## Interim technical rept.,

# Corporate Author:

## SYRACUSE UNIV NEW YORK DEPT OF CHEMICAL ENGINEERING AND MATERIALS SCIENCE

# Personal Author(s):

# Report Date:

## 1971-06-01

# Pagination or Media Count:

## 56.0

# Abstract:

The report contains the results of calculations on the effect of multiaxial stress states on the fracture ductility of solids. It is assumed that the solids in question follow a stress-strain law of the type sigma K epsilon to the nth power which holds both for the tensile case as well as for the case of effective stresses and strains. The multiaxiality of the stress state is expressed in the form of ratios, alpha sigma sub 2sigma sub 1 and beta - sigma sub 3sigma sub 1. The fracture ductilities are given in terms of ductility ratios, namely the fracture ductility for a given stress state epsilon sub F, alpha beta divided by epsilon sub TF, the tensile fracture ductility. The results are presented in the form of graphs with the fracture strain ratio as the ordinate, the stress ratio alpha as the alpha as the abscissa, the stress ratio, beta, and the strain hardening exponent n as parameters. Marin postulated a maximum fracture stress failure criterion. The calculations that were made in accordance with Marins criterion are labeled maximum stress criterion. Experimental studies have shown that the results are not in good agreement with this criterion. Therefore, Weiss has suggested a failure criterion based on a critical volume strain. In the calculations this criterion enters as a critical mean stress criterion. Author

# Descriptors:

# Subject Categories:

- Metallurgy and Metallography
- Mechanics