# Structural Mechanics Calculations of SiC/Mo-Re Composites with Improved High Temperature Creep Properties

## TL;DR

This paper designs a composite material for space reactors that reduces stress and improves high-temperature performance.

## Contribution

The novel use of gradient transition layers reduces thermal stresses in SiC/Mo-Re composites.

## Key findings

- Gradient layers between metal and ceramic phases reduce thermal stresses in composites.
- Optimized gradient layers improve stress distribution under operating conditions.
- Reduced stress in the alloy phase may extend high-temperature creep life.

## Abstract

In the present work, we design a laminated composite composed of molybdenum–rhenium alloy and silicon carbide ceramics for use in space reactors as a candidate structural material with neutron spectral shift properties. The influence of the internal microstructure on the mechanical properties is investigated by finite element simulation based on scale separation. The results of the study showed that the incorporation of gradient transition layers between the metallic and ceramic phases effectively mitigates thermally induced local stresses arising from mismatches in coefficients of thermal expansion. By optimizing the composition of the gradient transition layers, the stress distribution within the composite under operating conditions has been adjusted. As a result, the stress experienced by the alloy phase is significantly reduced, potentially extending the high-temperature creep rupture life.