Long-Term Life of Ni/Cu Bellows: Effect of Diffusion on Thermomechanical Properties

The aim of this paper is to discuss di erent couplings between di usion, recrystallisation/grain growth, strain/stress, heat transfer and thermo-mechanical behaviour of metallic materials. The understanding of these di erent physical phenomena is needed to predict the long-term life of mechanical parts in components. Some results are presented and further studies are suggested to improve the evaluation of the (inter)di usion and recrystallisation parameters in ne-grained electroplated Ni/Cu materials. To illustrate the coupling between elasticity and di usion, classical results in homogenisation consistent with the main di usion regime are used to predict the change in elastic moduli with time.