Brake disc : Residual stresses measurements by three complementary methods

For passenger's safety and to improve rolling stock maintenance, the French railway company SNCF is studying the optimization of mechanical components. As part of a project aimed at exploring brake disc properties, the Railway Testing Agency, which is part of the Rolling Stock Engineering Department, studied the residual stress levels reached in theses mechanical component by three complementary methods. These three methods are X-Ray Diffraction, DHD method and contour method. The XRD analyses were carried out in our laboratory while the deep drilling and contour methods were outsourced. This presents the results obtained by each of these three methods as well as their complementarity for an in-depth study of residual stresses.