Research Article
Nabaa S Radhi, Mohammad H H
Abstract
Functionally graded material (FGM) is new generations of composite materials where the properties are changed linearly according to the change in composition. This work presents the design, fabrication and characterization of multi NiTi shape memory alloys incorporated into single functionally graded materials. This design assumed to improve the general properties of NiTi shape memory alloys, especially the transformation temperature range. These materials are designed to have gradual microstructural or compositional variations within the body in one piece or single material. The powder metallurgy approach has been used extensively in preparing of NiTi alloys as well as the two models of functionally graded materials. The effect of layers composition, sintering time and temperatures was studied on the; microstructure as well as the developmental phases. Corrosion rate and characteristics as well as the toxicity of sintered materials are investigated also. Corrosion test results show that the current of corrosion (Icorr.) for SMA-FGM samples are less than that obtained at each layer (i.e., 19.02, 15.32 μA/cm2 for SMA-FGM1 SMA-FGM2) respectively, and Nickel ions percentage in Ringer solution after corrosion test show SMA-FGM1 SMA-FGM2 samples less than each layer.