Abstract:
Structural steel components tend to wear when exposed to corrosive and
cyclic loading environments. These components can be repaired by
welding on failure. This study studied the weld parameters and weld
quality (porosity, depth of penetration, and coating thickness), hardness,
corrosion, and wear resistance during repair welding. Mild steel samples
were weld coated by varying alternating (AC) and direct (DC) currents: 40
A, 50 A, 55 A, 60 A, 65 A, and 70 A. The base material used was AISI 1045
steel, and Castolin 6825 was used as the welding electrode. The results
showed that three wear mechanisms were dominant: abrasion, adhesion,
and delamination. The porosity in the coated samples increased with
increasing currents for both AC and DC. The welding current and current
type influenced the coating thickness and penetration depth. When dipped
in warm NaCl solution, the corrosion mechanism experienced by both sets
of coated samples was pitting corrosion. In both cases (alternating and
direct currents), the hardness values increased towards the coating
surface from the substrate.
