Abstract: As energy generation and manufacturing processes seek higher efficiencies, process temperatures continue to increase. These higher temperatures put strong demands on the structural materials used to build plant vessels, piping, heat exchangers, and other components.

Particularly for advanced nuclear reactors, economics dictate plant components with long design lives, extending beyond the available creep rupture test data. This means current plant designs are based on empirical extrapolation rules. Multiscale modeling provides a tool for accurately predicting material properties beyond the domain of existing experimental test data, leading to safer and more efficient plant designs.

I discuss a multiscale model for the creep-rupture properties of a common high-temperature structural steel and comment on the obstacles facing researchers trying to develop true ab initio multiscale models that can be used to design new metal alloys with better long-term, high-temperature performance.