Lubricity of microcrystalline glass on P91 alloy steel at 1150 °C

Lubrication and anti-oxidation are vital for hot metal forming process. The oxidation resistance and lubricity of microcrystalline glass with different Zr content on P91/H13 at 850 degrees C similar to 1150 degrees C were studied. High temperature tribo-tests of P91/H13 counterparts indicate that moderate Zr is beneficial to the formation of three sub-layers due to inter-facial and dissolution reaction of the steel and glass. This hierarchical structure present on the surface contains dendrites and the oxide grown by epitaxy in amorphous melt, which contributes to easy shearing and diffusion reduction of elements through physical isolation and ion shielding. This work provides guideline for the design of glass lubricant with excellent lubricity and oxidation resistance above 1000 degrees C.