Analysis of Mechanical Properties for the Gray Cast Iron Using Smaw Process with NiFe-CI Electrodes

Weldability of gray cast iron is poor due to the presence of graphite flakes which reduces the ductility. Welding of cast iron was conducted using shield metal arc welding process (SMAW). To analysis the cooling effects on welding strength, welding was carried out on samples with preheat, without preheat and post welding heat treatment. In this study was trying to emphasis on slowing the welding cooling rate by using insulation. Nickel based electrodes were preferred which provides soft, machinable, ductile deposit. The preheating treatment carried out at 350°C and stress relieving carried out at 621°C hold for 1hr and then cooled in furnace to room temperature. The weldability of each welding condition was evaluated through the tensile strength and hardness.