131773A condition-based structural integrity and remaining life model for austenitic stainless steelsClosedFeasibility StudiesInnovate UKThis feasibility study focusses on structural integrity issues arising from the continued life extension of the AGR fleet - in particular with the austenitic steels used in heat exchanger s for tubing and supports. Operating in the creep regime, these materials show considerable microstructural development in service, with consequent changes in mechanical properties. It includes an experimental programme comprising creep, tensile, and impact testing of pre-aged Type 316 steel, with associated metallographic studies. The aims are to assess the potential for a formal method of classifying microstructural development, a model of this development, and a preliminary model of the resultant mechanical behaviour. The deliverables will include demonstration software that estimates remaining creep life on the basis of observed microstructural state, using the preliminary model.