Integrated preparation and enhanced performance of high-melting-point ZrC–Mo multilayer graded materials

The materials used in astronautics fields are usually designed to withstand severe thermal stress induced by large temperature differences. Compared with homogenous materials, functionally graded materials (FGM) possess gradient properties and can be applied in harsh operating conditions. In this study, ZrC–Mo multilayer FGM were designed and prepared with three gradient compositions. The as-produced ZrC–Mo FGM exhibited the dense and homogeneous morphology and excellent interlayer bonding without visible defects such as cracks and pores. The results of oxyacetylene ablation tests indicated that compared with homogeneous ZrC-based composites, the ZrC–Mo FGM could better maintain integrity and avoid catastrophic damage. An effective property transition was established by the gradient design, which could relieve the stress caused by the difference in thermal expansion coefficient between ceramic and metal materials. The FGM in the composition of quadratic function nonlinear with higher Mo content show the optimized overall performance. The study provides a new strategy for developing promising candidate materials under ultra-high temperature conditions.