Hardening of weld with metastable austenite structure by surface deformation

Abstract

The study shows a technology comprising MIG deposition of cored wire like 50Cr18 with the subsequent surface deformation. Specially developed device realizes adjustable ball rolling load. The structure of the weld includes a large share of metastable austenite, which transforms to hard martensite at loading. The measuring shows that the technology provides an increase of the sample's surface hardness from 40 HRC to 54 HRC and decrease it's roughness from Ra 1,2 to Ra 0,4. The results allow using the technology applying to hydraulic pistons. © Published under licence by IOP Publishing Ltd.