Effects of Laser Hardening Treatment on the Wear Properties of the Vanadis 4 Extra and Vanadis 10 Tool Steels

Vanadis tool steels which are trademarks of the Uddeholm AB Company are high vanadium content (along with chromium and molybdenum) steels with unique mechanical properties such as very high wear resistance along with a good machinability, dimensional stability and grindability. They are widely used in blanking operations, stamping, deep drawing, cutting and slitting blades. Microstructural features of Vanadis steels are directly depended upon the distribution of different carbide phases. In this study, the effects of laser hardening on the Vanadis 4 extra and Vanadis 10 grade tool steels are investigated. Following the laser hardening route on the samples, abrasive wear behaviour, microstructural changes and microhardness values were determined. Wear test results and microhardness data are correlated with the resulting microstructural features. It was found that the increase in microhardness and thus wear resistance is attributed to the finer grain size for both of the Vanadis 4 extra and Vanadis 10 grades. The results were also compared with the same Vanadis grade samples which were hardened using heat treatment processes. It is found that there is a considerable increase in the microhardness values for the Vanadis 10 samples. The data shows 100.6% increase in the laser treated samples compared to the heat treated Vanadis 10 samples. Only a very slight increase (about 4%) of the microhardness value for the laser treated Vanadis 4 extra was recorded.