Mechanical and thermomechanical characterization of Ni50-x Ti50Cux(x=2, 5, 10at%) with morphological studies

Shape memory alloys TiNi-xCux (x = 2, 5, 10 at%) were made in a traditional vacuum arc remelting furnace (VAM). The alloy was characterized after heat treatment in an inert atmosphere. X-ray diffraction (XRD), differential scanning calorimeter (DSC), Field emission scanning electron microscope (FESEM), and Energy Dispersive Spectrometer (EDS) were used to investigate the impact of replacing Ni with Cu in Equiatomic NiTi Shape memory alloy (SMA). The results obtained from XRD revealed the formation of monoclinic martensite and austenite phases and the presence of an intermetallic Ti2Ni phase. The EDS results revealed that there are some minor deviations in the compositions. The results of the differential scanning calorimeter revealed that the phase transformation sequence of all the samples are in a single- stage form B2 to B19' and the transformation hysteresis is decreased as Cu content increases. The microhardness results confirmed that the Cu addition on equiatomic NiTi increases the hardness due to the formation of intermetallic secondary phases and its distribution on the matrix. Copyright (C) 2022 Elsevier Ltd. All rights reserved. Selection and peer-review under responsibility of scientific committee of the International Conference on Advanced Materials and Mechanical Characterization (ICAMMC 2021).