TENSION-TORSION BEHAVIOR OF SINGLE-CRYSTAL SUPERALLOYS - EXPERIMENT AND FINITE-ELEMENT ANALYSIS

This article investigates the macroscopic behavior of single-crystal superalloys under torsion or tension-torsion loadings. To this end, specific tests were performed at room temperature, on tubular specimens equipped with micro strain-gages for local deformation measurements. The comparison between the theory and the experiment concerns both the stress-strain hysteresis loop and the yield surface. The analysis of the experimental results requires a finite element analysis, due to the complex stress redistributions arising in the specimen. This is made with a crystalline model, which appears to be in good agreement with the experimental data.