A new approach to creep data assessment

New relationships, incorporating the activation energy for matrix diffusion (300 kJ mol−1) and the ultimate tensile strength values at the creep temperature, allow effective rationalization of the multi-batch stress rupture properties for Grade 92 steel (9Cr–0.5Mo–1.8W–V–Nb). These approaches lead to straightforward procedures for extrapolation of short-term results, with creep life measurements from tests lasting up to only 5000 h providing reasonable estimates of 100,000 h rupture strengths. Validation of this new methodology would therefore offer the prospect of cost-effective acquisition of long-term creep design data.