Effects of Ag and Cu Nanopowders on Mechanical and Physical Properties of Niti Shape Memory Alloy

Abstract

Nickel Titanium shape memory alloy reinforced with nano particles have different and many uses in multi implant applications due to their excellent characteristics. The present work is aimed at studying the preparation of nitinol reinforced with nano particles of copper and silver. A base alloy of (55% Ni + 45%Ti) has been prepared by using powder metallurgy technique with  a determined suitable compacting pressure of 650 MPa and sintering for 5 hours at 850? C in argon gas furnace. Samples with 0.5wt% of Cu or/and 0.5wt% of Ag nanoparticles were prepared. Mechanical and physical characterization included microhardness, porosity, shape memory effect, microstructure, x-ray diffraction and particle size analysis. The results showed that the hardness value increase at 0.5 wt% of Cu and 0.5wt% of Ag together to 287 Hv and to 5.3 in shape memory effectwhile the porosity decreased to (23.1) for alloy with the same percent.