Modelling self healing creep steel

Advances in self-healing creep steels are driven by the understanding of its mechanism. Previous work on self-healing creep metals has shown selective precipitation inside the creep cavities, which has a beneficial effect on the creep lifetime. This effect occurswhen a solute supersaturation exists at the creep temperature. In the case of self-healing creep steels, the precipitation of gold was found to have an exceptional effect. Gold precipitation was found to be efficient because of the atomic size mismatch of gold and iron, which induces a high selectivity for precipitates to form inside creep cavities and not in the bulk. However, gold is not the most widely used alloying element in steel, to put it mildly. Ideally the self-healing effect could be achieved by another solute element dissolved in steel. In order to identify some other possible solute element for self healing creep steels, the mechanism must be understood. In this thesis the mechanism of self healing creep steels, andmetals in general, is investigated.