Influence of mechanical alloying and preheating on fabrication of NiTi alloy by combustion synthesis

Subject Areas :

Ali Reza Sadegi Aval Shahr ¹ , Hassan Mostajab o daveh ² , Abolfazl Babakhani ³ , Mojtaba Zebarjad ⁴ , Akram Salehi ⁵

1 - کارشناس ارشد، مهندسی پزشکی و عضو گروه پژوهشی مواد، جهاد دانشگاهی مشهد
2 - دانشجوی دکتری، مهندسی مواد، دانشگاه سمنان، مشهد
3 - دانشیار، گروه مهندسی مواد، دانشگاه فردوسی مشهد، دانشکده مهندسی، مشهد
4 - استاد، گروه مهندسی مواد، دانشگاه شیراز، دانشکده مهندسی، شیراز
5 - کارشناس ارشد، مهندسی مواد و عضو گروه پژوهشی مواد جهاد دانشگاهی مشهد

Received: 2016-04-03 Accepted : 2016-04-03 Published : 2017-02-19

Keywords: XRD, Milling, Thermal Explosion, Preheating, NiTi Shape Memory Alloy,

Abstract :

In this study Ni and Ti with 50 at. % Ni powders were milled and the cylindrical performs obtained by uniaxial cold compaction under 150 MPa pressure. Porous Ni/Ti specimens were synthesized by thermal explosion (TE) at different preheating temperatures (350 °C, 400 °C, 500 °C and 600 °C) and milling times (0.5, 1 and 2h). The effect of preh­­­eating temperatures and milling times on microstructure of final products were investigated by X-ray diffraction analysis (XRD), optical microscopy and scanning electron microscopy (SEM). NiTi shape memory alloy with other secondary intermetallic compounds and elemental powders were observed in the final products. Results showed the dominant phase was NiTi in the sample that milled for 1h and preheated at 400 °C.