Mechanical Properties of Nitrided Layer after Laser Modification

The aim of this work was to study the microstructure and friction coefficient hybrid surface layers, produced by a controlled gas nitriding laser modification. Nitriding is well-known technique thermo-chemical treatment, applied in order produce layers improved hardness wear resistance. phase composition growth kinetics diffusion layer can be using with changeable potential. 42CrMo4 steel treated composite technology hardening. processes were carried out at temperature 580 °C for 8h. Next, nitrided laser-modified TRUMPF TruDiode 3006 maximal power 3 kW two beam powers (P): 0.53 0.62 kW. Then, properties investigated optical microscopy, Vickers tester testing machine. subjected tests ball-on-disc method room temperature. results showed that consisted re-melted heat-affected zones which martensite mainly occurred. Additional treatment effectively increased hardness, especially zone, as well depth hardened layer. after modification hest tretment good coefficien. curve characterized large fluctuations. Compared , increase resistance surface. effect LHT on tribological ambiguous. Although relatively low value average (0.46) calculated layer, course fluctuations extended grinding-in time. Simultaneously, very smooth LHT. However, higher, obtaining 0.60 0.57 P=530 W P=620 W, respectively. Keywords: Nitriding; Laser Heat Treatment; Microstructure; Wear Resistance; Microhardness