Processing And Characterization Of Shape-Memory-Alloys Synthesized From Niti Pre-Alloyed Powders

摘要

Powder metallurgy is a promising route to manufacturing near-net-shape NiTi components for industrial applications. In this study, NiTi shape-memory-alloys were produced by cold-pressing and sintering, starting from gas atomised pre-alloyed powders. The influence of the thermal treatments and sintering atmospheres on the impurity content was studied in order to achieve optimum shape memory effect. A detailed characterization of the different samples was performed using X-ray diffraction (XRD), differential scanning calorimetry (DSC) measurements and scanning electron microscopy. The shape memory effect was quantitatively characterized using a special apparatus measuring strain versus temperature under constant load.