Structure and ablation behavior of “Z-pins like” M-MC1-x (M = Zr, Hf) gradient cermet rods prepared by carbon diffusion in situ reaction method

In this study, "Z-pins like" M-MC1-x (M = Zr, Hf) gradient cermet rods were prepared by the carbon diffusion in situ reaction method, and the effects of different heat treatment temperatures on the microstructure of MC layers in "Z-pins like" M-MC1-x gradient cermet rods and the ablation behavior of "Z-pins like" M-MC1-x gradient cermet rods were investigated. The results showed that "Z-pins like" M-MC1-x (M = Zr, Hf) gradient cermet rods formed gradient MC layer after heat treatment, and the thickness of MC layer increased with the increase of heat treatment temperature, and the in situ reaction method improved the bonding conditions of different phase interfaces. The ablation performance of "Z-pins like" M-MC1-x cermet rods was good. After ablation, the "Z-pins like" M-MC1-x cermet rods formed multilayer structure inside, from the surface oxide layer to the substrate: partially molten MO2 layer, loose MO2 skeleton, MO2 layer formed by a large number of nanoscale microcrystalline aggregates, dense MCxOy layer and unoxidized MC1-x and M-MC1-x eutectic phases.