Development of a New PM Tool Steel for Optimization of Cold Working of Advanced High-Strength Steels

Abstract

In the present study, Uddeholm Vancron SuperClean cold work tool steel was investigated concerning wear resistance and fatigue strength, using laboratory and semi-industrial tests. The Uddeholm Vancron SuperClean was designed with the help of ThermoCalc calculations to contain a high amount of a carbonitride phase, which was suggested to improve tribological performance of this tool steel. In order to investigate the tested steel, galling tests with a slider-on flat-surface tribotester and semi-industrial punching tests were performed on an advanced high-strength steel, CP1180HD. Uddeholm Vanadis 8 SuperClean containing only a carbide phase and Uddeholm Vancron 40 containing a mixture of carbides and carbonitrides were also tested to compare the performance of the tool steels. The microstructure and wear mechanisms were characterized with scanning electron microscopy. It was found that the carbonitrides presented in Uddeholm Vancron SuperClean improved its resistance to material transfer and galling. Semi-industrial punching tests also confirmed that Uddeholm Vancron SuperClean cold work tool steel also possesses enhanced resistance to chipping and fatigue crack nucleation, which confirms the beneficial role of the carbonitride phase in wear resistance of cold work tool steel.