Repairing the surface grooves of St37 structural steel using flame spray welding

Abstract

In today’s industry, preventive measures for the preservation and repair of devices and equipment are extremely important. Various welding methods are used for repairing the surface crack of metal pieces in order to improve their mechanical properties and increase their useful life. In the present study, the performance of flame spray welding using pure iron powder is evaluated in repairing the surface grooves of St37 structural steel. First, five groups of specimen (one control group and four grooved steel groups with 0.5 mm groove tip, 10 mm length and 0.5, 0.8, 1 and 1.3 mm groove depths) were prepared. Then, the repair was performed. The results showed that after repairing the surface groove via flame spray welding using pure iron powder, the tensile strength and yield strength of the repaired specimens with the groove depths of 0.5 and 0.8 mm were achieved to control ones, but the elongation was decreased, which was still acceptable for engineering applications (module of toughness of 74.2 MJ) for the repaired specimen with the groove depth of 0.5 mm.