Torsional Performance of Driveshafts for Vehicle Driveline Applications

Torsional fatigue tests have been performed on smooth and notched testpieces of induction-hardened steels, as part of a programme to develop techniques for life prediction and materials selection for CV joint driveshafts, to underpin future downsizing. The results demonstrate the improvements in performance that can be achieved through increasing case depth and materials selection. The observed performance is related to the basic material properties and the failure modes in torsion. The need to further develop fundamental multiaxial life prediction methodologies so as to account for the complex material behaviour induced by the imposed stress state is emphasised.