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The present paper describes a study that attempts to develop the use of thermal barrier coatings for industrial foundry applications. A wide range of tool steel specimens coated with plasma-sprayed, thermal barrier ceramics having different compositions were tested in thermal fatigue by repeated immersion in liquid aluminium. Then, residual stress measurements performed by neutron diffraction on specimens coated with the ceramic that exhibited the longest thermal fatigue life showed the evolution of the residual stress profiles in the near-interface layers of the substrate. Synchrotron radiation measurements were attempted in the coating and in the vicinity of the interface.

The residual stress field in shrink-fit disc-ring systems was investigated in the framework of a general research, the final goal of which is to establish optimisation criteria for the joining procedure in the AA6082 aluminium alloy. In particular, two different procedures were considered: the traditional thermoelastic and an innovative thermoelastoplastic coupling. The two processes were simulated by finite element calculations, which were optimised by comparison with existing analytic models. Neutron diffraction experiments were carried out on samples obtained by the two procedures. The comparison between the theoretical and experimental results showed a satisfactory agreement. Small differences found were ascribed to already existing residual stresses, which were actually measured in uncoupled samples.