A methodology for evaluating different combinations of materials specifications for extreme environment applications is presented. This new approach addresses the materials selection problem using a multicriteria stringency level methodology that defines several thresholds obtained by analyzing different prediction models of irradiation embrittlement and hot cracking. To solve the conflicts among thresholds as provided by the different prediction models, a multiobjective approach is carried out. Materials for reactor pressure vessels have been considered as case study. It has been concluded that the best option to manufacture a pressure vessel for a pressurized water modern reactor is the selection of German manufacturing standards. Finally, a sensitivity analysis of the proposed methodology has been performed to evaluate the divergences between the single stringency level methodology and the new proposal including multicriteria decision making aspects… See all…