Formation of Build Up Layers Microstructure by Arc Automatic Overlay Welding Using Secondary Raw Material Powders

Abstract

Microstructure and properties of structural steel subjected to overlay welding with secondary materials powder is investigated. Crushed glass, grinding wheels (SiC), hard metals plates, high speed steel and cast iron chips as well as marble powders were used in automatic overlay welding of steel by low carbon wire. Powder spread over the steel surface and melted by continuously supplied wire arc enabled to obtain layers with graphite and carbides inclusions in the matrix; hardness of the matrix depends on the phases contained in it: martensite, troostite and residual austenite as well as secondary carbides. Depending on materials used for overlay welding the layers were obtained which abrasive wear resistance became equal to that of high alloyed hardened tool steel. Wear of these layers is much more less in comparison with low alloyed hardened tool steel.