Failure Analysis of Cast Irons Under General Three-Dimensional Stress States

Observations of microscale behavior of cast irons indicate that considerable plastic flow occurs between microflaws prior to rupture. Therefore, the plastic limit load for small representative volume elements of material treated as structures should be a close approximation to the load at rupture. A representative volume element of cast iron is analyzed using limit analysis techniques to obtain bounds on the limit, or failure, surface under three dimensional average stress. Comparisons with other cast iron failure criteria and experimental data are made.