How does vanadium help tool steels keep their hardness at high temperatures?

Vanadium helps tool steels maintain their hardness and cutting ability at high temperatures primarily by forming carbides with the carbon present in the steel.12

In addition to this carbide formation, vanadium acts as a grain refiner for the steel matrix. By incorporating strong carbide-forming elements like vanadium, molybdenum, and tungsten, tool steels are engineered to be wear-resistant and stable, allowing them to remain effective even when subjected to the heat generated during high-speed machining and shaping processes.134