Experimental study of ductile fracture of tubes under combined tension/torsion

Abstract

This experiment sought to compare the results of an experimental torsion test on a specimen of 1045 steel with a torsion simulation in the ABAQUS FEA software program. A simulation of a tension test on a round bar of 1045 steel was first executed to determine the correct stress-strain curve for 1045 steel. A torsion specimen was designed based on the constraints of the testing machine, and the torsion test was carried out. A model of the specimen was constructed in ABAQUS using the results of the tension simulation, and a torsion test was simulated. The simulation accurately predicted the shape of the experimental torque vs. twist curve, but the simulated values were 7% higher than the experimental values in the plastic region. The specimen fractured at a rotation of 430 with a plastic strain of 1.013. This was 2.4 times higher than in the tension simulation, where the specimen failed at a strain of 0.427.