Compositional Modification of Tool Steel to Improve Its Wear Resistance

摘要

The high hardness property of hot working steel is not always an advantage as several defects can occur, which reduce the productivity and reliability of the hot forming processes. In the case of laser cladding technologies employed during deposition, porosity can appear in the clad material. In the current study, different strategies are explored to avoid porosity of hot working tool steel during laser cladding operations by increasing the steel's ductility without affecting its wear resistance. Laser cladding of AISI H13 powder mixing with different amounts of Ni was carried out on a sample of reference tool steel (similar to AISI H13). An optical microscopy analysis and hardness measurements of the clad material permitted us to select the most desirable mixed powder in order to improve the wear behavior of the hot working tool steel. With the aim of comparing and quantitating the improvements achieved in terms of their wear resistances, wear tests were carried out on the hot working steel and the modified sample using SRV Optimol tribometer (Reciprocating Sliding Fiction and Wear Tester) at temperatures of 313.15 K and 473.15 K (40 degrees C and 200 degrees C). The results showed an improvement of the wear behavior for a specific compositional modification.