A. PhukaoluanA. KhantachawanaP. KaewtatipS. DechkunakornN. AnuwongnukrohP. SantiwongJ. KajornchaiyakulKing Mongkuts University of Technology ThonburiMahidol UniversityThailand National Metal and Materials Technology Center2018-05-032018-05-032011-09-23Applied Mechanics and Materials. Vol.87, (2011), 95-10016627482166093362-s2.0-80052951319https://repository.li.mahidol.ac.th/handle/20.500.14594/11887This study aims to investigate mechanical properties and transformation behavior of TiNiCu shape memory alloys to obtain optimal conditions for utilizing as orthodontic wires. TiNi binary alloys with Ni-content 50.6 at.%, TiNiCu alloys with Cu-content ranging from 5 to 10 at.%, were prepared. The alloys were melted by electrical arc-melting method and then homogenized at, 800°C for 3600 s. The alloys were subsequently sliced into thin plates (1.5 mm) by EDM wire cutting machine. To evaluate mechanical properties, the specimens were cold-rolled with 10, 20 and, 30%, followed by heat treatment at 400°C and 600°C for 3600 s, respectively. A Differential Scanning Calorimeter (DSC) was used to detect transformation temperatures. Mechanical properties were evaluated by micro hardness and three-point bending tests. The results showed that transformation temperatures were strongly increased with increasing Ni-content. Moreover, the decrease in transformation temperature after increasing level of cold-rolling reduction ratio suggests that internal stress can depress transformation. However, internal stress seemed to support the introduction of superelasticity for each specimen. In addition, specimens heat treated at 400°C have more appropriate properties as orthodontic wires than those heat-treated at 600°C due to the remaining effect of cold-working. These results can be take into consideration for optimizing alloy composition and mechanical properties of TiNiCu shape memory alloys for orthodontics wires purposes. © (2011) Trans Tech Publications.Mahidol UniversityEngineeringConference PaperSCOPUS10.4028/www.scientific.net/AMM.87.95