Study on the influence of post-processing parameters over microstructure and metallurgical properties of NiTi alloy

Post-process heat treatments are conventional methods used to minimize porosities and improve the microstructure of metallic parts. It can also increase the hardness value and help tailor the mechanical properties of the part. On the other hand, the heat treatment process includes several steps and can be a costly and time-consuming procedure. The different variables and parameters in heat treatment can make this process even more complicated. Utilizing optimal heat treatment parameters decreases the cost and operation time and results in higher finish quality and better device performance. This study investigates the influence of heat treatment parameters on microstructure and metallurgical properties of NiTi shape memory alloys to find the optimum values for post-processing. The samples were cut in equally sized dimensions, and they were treated using the same equipment. Various ranges of heating duration and temperature were considered for the experiments. It was revealed that, regardless of parameters, the heat treatment process can bring about better compositional characteristics and hardness properties of NiTi. However, some particular sets of heat treatment parameters resulted in higher quality and more favorable final properties.

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