Comparative analysis of electrical and hot water actuation of shape memory alloy spring using thermo-mechanical cycle test bench

摘要

The optimal design and analysis of hot water actuated shape memory alloy spring is presented. Smart materials exhibit special properties that make them a preferred choice for industrial applications in many branches of engineering. The serviceable properties of a Ni-Ti piece can be improved by altering the energy source. With hot water actuation, as the temperature reaches 70 °C - 90 °C, spring gets fully compressed for the first few cycles followed by loss in actuation. The actuation loss is then studied with different characterisation methods such as thermo gravimetric analysis (TGA) and scanning electron microscopy (SEM). With SEM results, it can be strongly recommended that the energy source is sufficient for actuation (not affecting too much the structure). Results observed from TGA shows high oxygen content at lower temperature, suggest the need of conducting experiments in inert atmosphere. For the validation of hot water actuation, comparative analysis between electrical and hot water actuation is done. Graph shows that, there is a good agreement between both the methods. In addition to this, the application of hot water actuation is some micro-devices like micro-valve, drug delivery, directional control valve, also in engine in place of thermostat valve etc.