Microstructure and mechanical properties of friction-stir welded St52 steel joints


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KÜÇÜKÖMEROĞLU T., AKTARER S. M., Ipekoglu G., Cam G.

INTERNATIONAL JOURNAL OF MINERALS METALLURGY AND MATERIALS, vol.25, no.12, pp.1457-1464, 2018 (SCI-Expanded) identifier identifier

Abstract

The aim of this work is to investigate the mechanical properties and microstructures of friction-stir welded (FSWed) St52 structural steel joints. In this study, St52 steel plates with a thickness of 4 mm were butt-welded by friction-stir welding (FSW) using a tungsten carbide tool having a conical pin. The microstructure of the welded zone consists of equiaxed fine ferrite, grain boundary ferrite, Widmanstatten ferrite, and aggregates of ferrite + cementite. The microhardness measurements showed that the hardness of the welded zone was significantly higher than that of the base metal. The FSWed St52 joint exhibited a significant strength overmatching in the weld region and a strength performance similar to or slightly higher than that of the base plate.

The aim of this work is to investigate the mechanical properties and microstructures of friction-stir welded (FSWed) St52 structural steel joints. In this study, St52 steel plates with a thickness of 4 mm were butt-welded by friction-stir welding (FSW) using a tungsten carbide tool having a conical pin. The microstructure of the welded zone consists of equiaxed fine ferrite, grain boundary ferrite, Widmanstatten ferrite, and aggregates of ferrite + cementite. The microhardness measurements showed that the hardness of the welded zone was significantly higher than that of the base metal. The FSWed St52 joint exhibited a significant strength overmatching in the weld region and a strength performance similar to or slightly higher than that of the base plate.