Formability studies on Ni-Ti shape memory alloy using laser forming technology

Laser forming is an advanced manufacturing process which is extensively used in automotive and manufacturing industry by deforming metallic and non-metallic sheets. In this process, a continuous fiber laser is irradiated over Ni-Ti sheet. As the laser beam imbibed over the sheet, a step temperature thermal gradient got induced across the thickness of the sheet. The bending moment arises due to uneven thermal stresses leads to the deformation of the sheet without using any external forces. This paper shows the experiments performed on Ni-Ti sheets of dimension 60mm×50mm with a maximum power of 50W. The process parameters which were varied are number of passes (10 to 20), power (30W to 50W) to get the maximum bending angle with a uniform spot diameter of 2mm. The study between variations of the bending angle with process parameters is done. After this, the characterization of samples was done using differential scanning calorimeter (DSC) and the changes in phase transformation of Ni-Ti SMA with respect to change in different powers and number of passes is studied. (paper)