Residual Stress Evaluation in Railway Wheel/axle

Abstract

The railway industry is interested in studying the stress field at the interface between a railway wheel and its press fitted axle. The neutron diffraction technique provides a powerful tool for stress field investigations deep within the material. But the distance of neutron penetration is too high. For neutron diffraction strain measurements, a new method is proposed, involving drilling access holes to minimise the neutron path length within the material. The first step consists of determining the high-concentrated stress zone and of determining the influence of the drilling parameters on the stress. The second step is to perform neutron diffraction strain measurements. These measurements gave some elastic micro-strain values at the wheel/axle interface whose are of the same order of the values obtained by numerical simulation. Values are in good agreement with each other with a gap of 80 µε, which is near to the neutron diffraction technique sensitivity.