Study of the Effects of Welding Process on the Microstructure of Worn Carbon Steel Shaft

摘要

This paper presents a new procedure to repair a worn, low carbon steel shaft by use of discontinuous arc welding, and studies the effect of the proposed methodology on the microstructure of the welding area. The aim of the proposed methodology is to repair locally the rotary shafts of mechanical equipment, which are usually damaged at the supporting zone. The compensating method is used to repair the damaged area by adding a thin layer of metal to compensate for the shortage in diameter as a result of erosion. The repair should be carried out without exposing to rising temperature, which is the main cause of stress concentrations and initiation of fatigue cracks. The results were obtained by microscopic analysis of the welded area and include mechanical properties for the obtained samples. The repaired area contains soft crystals and an increase in hardness above 41%. This indicates that the wear resistance has been improved, while preserving the tension strength as it was before repair.