Abstract: Hard facing is a process of depositing a layer of material on the base metal or substrate either to develop the surface features like corrosion resistance, Hardness, Toughness & Strength of the material etc. or to get the required size of dimension or to repair worn out products. Taguchi technique is applied for the optimization. Oxy-Acetylene gas welding process and Mild Steel material is used for hard facing. In this project a detailed experimentation is done in which the Electrode speed is primary component which impact both bead width and depth of penetration1 & the Hard Faced specimen absorbs more energy than that of the specimen before hard facing and Hard Faced material is 114 BHN harder than the normal gentle steel and Micro-Structural test shows the specimen before hard facing, uniform structure pattern of light Ferrite and dark Paralyte and after Hard Facing shows the structure pattern of Temper Marten site.
Keywords: Hard Facing, Oxy-Acetylene Gas welding, Taguchi technique, impact test, hardness, Micro-structural test.