Tribological performance of hot-stamping tool steels with different carbide types and contents

The use of hot stamping in the manufacture of automotive parts is increasing; therefore, new materials that allow greater productivity are a current challenge. In this context, we investigated the tribological behavior of two tool steels: 1.2344, which is still widely used, and a new grade, CP2M®. They were heat-treated in a salt bath to achieve similar hardnesses by selecting adequate tempering temperatures. Tribological tests were conducted in two modes (reciprocating and progressive scratch) to evaluate wear mechanisms. Abrasion mechanism was important for both tested temperatures, but more intense at 200 °C. Hard (Mo, V)C carbides were predicted by thermodynamic simulation and detected using a combination of nanoindentation and EDS. Compared to 1.2344 steel, CP2M® steel promoted a reduction in wear rates of up to 67%. The highest hardness of CP2M® steel did not correspond to the best performance, due to the brittleness of the microstructure during the abrasion process.