Nitinol shape memory alloy spring

Manufacturing, over the years, has evolved through three revolutions brought out by the impact of mechanization, electricity and Information Technology. The update in manufacturing has its root of intelligence. Necessity of miniaturization is shifted the use of conventional actuators with smart actuators. Conventional actuators generally produce the power in proportion to their volume, which reduce their application in micro applications. A concise review of the recent developments within nearly ten years on shape memory alloys has been presented. Besides other available shape memory alloys, Nitinol(Ni-Ti) is preferred due to its array of characteristicslike light weight, high power to weight ratio, noiseless operation, ease of actuation and muscle like movement. Shape memory effect and pseudo-elasticity play a crucial role in smart materials. Various actuation modes (Joule heating, hot water, laser assisted) and cooling methods are tabulated for Ni-Ti. The different forms of Nitinolare commercially available, but spring is used specially, due to its coiled structure.