Microstructural and mechanical characterization of Ti6Al4V refurbished parts obtained by laser metal deposition

Thin sections of Ti6Al4V based aeroengine structural material was refurbished using laser metal deposition (LMD) technique. The thermal gradient and cooling rate was strategically controlled through the appropriate selection of laser process parameter such as laser power, scan speed and powder feeding rate. At a laser power of 1500 W and at a scan speed of 600 mm/min, the deposited layer is free of cracks and pores with good metallurgical bonding to the substrate as well as between the layers. The β to αˈ martensite phase transformation was prevalent in the deposited region which marginally increased the hardness. The ultimate tensile strength (UTS) of LMD was found to be 900 MPa which is slightly lower than the base UTS of 950 MPa. The LMD fails due to brittle fracture with traceable elongation.