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The acetabular shell mobilization is the main long-term complication in total hip replacement. Metal-back fracture has also to be considered among the possible causes of shell mobilization. A case is presented of bilateral acetabular shell mobilization due to the trabecular covering de-soldering from the metal-back in a 43 year-old patient, 13–14 years after the first surgery.

Neutron Diffraction shows that plastic pre-deformation and heat treatments have opposite effects on the residual stress in Al–SiCp composites. The thermal micro residual stress is relaxed or even reversed by pre-strains above 0.2%, but restored by heat treatments. The sense of relaxation changes above 400 °C (the mixing temperature).

In this paper, we report on the instrumental and technical characteristics of the new strain dedicated diffractometer developed at the LLB. A new sample line has been constructed in order to support very big samples, up to 500 kg in weight. It is equipped with an X – Y – Z translation tables and ω rotation. In this way, residual stress field in real industrial components can be evaluated Main characteristics and future improvements are outlined.

The present paper is concerned with the development of a thermal barrier coating resistant to liquid aluminium for an industrial foundry application. The material studied is a stabilised zirconia plasma sprayed on a tool steel. Thermal fatigue experiments by repeated immersion in liquid aluminium were performed on coated specimens, in order to optimise its thickness and composition. Residual stress measurements by neutron diffraction were performed on two thermal fatigue specimens: a reference sample, non-tested in thermal fatigue, and a specimen submitted to approximately 1000 thermal cycles. It appeared from these experiments that the residual stresses evoluated from an initial compressive state to a tensile state after thermal cycling. This inversion of residual stresses currently observed on industrial tools is known to be due to the combined effects of thermal fatigue and creep increased by structural softening (decarburation), and may be the principal cause of the coating's failure.