Laser clading of Inconel 625 on ASTM A575 steel

In this research, the microstructure of Inconel 625 cladded layer on ASTM A575 steel has been investigated. By examining different parameters, the optimal single-pass sample with the least amount of dilution, porosity and fusion and suitable wetting angle was determined. Then cladding process with the optimal parameter was performed. The microstructure of the cladding layer was evaluated from the base metal to the top. Due to different cooling rates, dendritic morphologies were observed at different distances. Also, the cladding layer was free of any cavities, porosity and cracks and its thickness was 0.9 mm (900 micrometers). The results of (XRD) and (EDS) analyzes indicate thatthe γphase is formed and there is a relatively uniform distribution of elements in the cladding layer. These results also indicate that no change in the chemical composition of the substrate surface was achieved near the interface.The hardness test results also show that the hardness starts from 450 VHN at the top surface and reaches to 135 VHN in the base metal with a gentle slope. This slope of hardness can be attributed to the cooling or heating rates of the substrate.