Laser Surface Alloying of Some Steels from SiC Predeposited Powders

Résumé

For the purpose of studying the possibilities of increasing the wear resistance, specimens of three steels with 0.2%C, 0.46%C and 1%C were surface alloyed with reinforcement from overlapping pastes with green SiC hard particles with the granulation 800 and 320. The melting of surface layer was performed by CO₂ continous wave laser on a numerical x-y table. On these specimens the micro structural characteristics, geometry of molten zone, micro hardness variation in the alloyed layer depth and the HV5 hardness on a laser processed surface were determined, which allowed defining the added material with the best hardening effect. The conditions to obtain compact surface layers with 2-3 time higher hardness than the base material were determined.