Modification of surface layers of quick-speed powdered metal steels using welding heat sources

Abstract

Powdered metal steel S390 and its equivalents are manufactured in a traditional way, that is, steel 10-4-3-10 (SK10V) which is subjected to modification of its surface layer. An analysis was made of the changes to the structure and mechanical properties of the above-mentioned steels at each individual stage of a heat treatment process carried out after soft annealing, quenching, tempering, and joint penetration surface treatment. The scope of this analysis included optimization of the joint penetration parameters, macro-, and micro-testing with utilization of scanning and light microscopy, preliminary tests of phase composition as well as comparative hardness measurement. The major practical purpose of the experiment was to assess the feasibility of using welding heat sources for joint penetration surface treatment of quick-speed steels.