Thermo-electro-mechanical characterization of anode interfaces at operating conditions

A large amount of energy is lost at the interface between materials in electrodes, reducing process energy efficiency. Thus, the characterization of thermo-electro-mechanical behaviour of the interfaces is necessary to support the numerical modelling as an essential step in improving the design of the anode connection. Experiments have been performed on carbon-cast iron-steel samples taken from the anode assembly. The samples have been designed and prepared in such a way that they are representative of the industrial sealing process.Some links between roughness and electrical resistivity have already been established in other studies [1]. In the present investigation, roughness measurements using laser profilometry have been carried out on samples subjected to compressive stress up to 2 MPa. Results have shown that loading effect is negligible on the asperities deterioration between the carbon-cast iron interfaces at this pressure.The obtained values of thermal contact resistance (TCR) and electrical contact resistance (ECR) are in good agreement with the experimental data published in the literature, but still higher than those of the theoretical contact model. This study leads to the development of a new constitutive law for electrical and thermal contact resistance as a function of temperature and pressure.