TY - JOUR ID - 34970 TI - THE AGING EFFECTS IN NiTi SHAPE MEMORY ALLOY WIRE JO - The International Conference on Applied Mechanics and Mechanical Engineering JA - AMME LA - en SN - 2636-4352 AU - Özkul, I. AU - Sampath, V. AU - Canbay, C. A. AU - ElFawkhry, M. AD - Department of Mechanical Engineering, Faculty of Engineering, Mersin University, Mersin, Turkey. AD - Department of Metallurgical and Materials Engineering, Indian Institute of Technology Madras, Chennai-600 036, India. AD - Department of Physics, Faculty of Science, Firat University, Elazig, Turkey. AD - Central Metallurgical Research Laboratory, Cairo, Egypt. Y1 - 2018 PY - 2018 VL - 18 IS - 18th International Conference on Applied Mechanics and Mechanical Engineering. SP - 1 EP - 8 KW - NiTi KW - DSC KW - XRD KW - aging DO - 10.21608/amme.2018.34970 N2 - ABSTRACTShape memory alloys occupy a niche position in the domain of advanced materialsthat have great relevance to medical, engineering, commercial as well asmiscellaneous applications. The transformation temperatures of the alloys areimmensely important since they decide the specific applications of the alloys in afield. These temperatures are influenced by a host of factors, including compositionand thermo-mechanical history of the alloy. In fact, due to continued usage also thetransformation temperatures are shifted due to what is known as functional fatigue,which is caused by the build-up of defects within the alloys during use. The horizon ofusage of shape memory alloys is ever widening. In the present study, therefore, theeffects of aging on the transformation temperatures of NiTi alloys are explored. Themartensitic transformation temperatures of the alloys were measured by differentialscanning calorimetry, while their microstructures were investigated by opticalmicroscopy. The results show that the aging temperatures as well as the holdingtimes influence the microstructure, which directly affects the transformationtemperatures. Aging at high temperature induces precipitation, leading to an increasein the Ti content of the matrix. This in turn caused an increase in the transformationtemperatures. On the other hand, aging at low temperature caused stress reliefleading to a shift in the transformation temperatures. UR - https://amme.journals.ekb.eg/article_34970.html L1 - https://amme.journals.ekb.eg/article_34970_2dab159a89d5b2a8f1ce45615d1493ac.pdf ER -