Author
Abstract
Nickel-Titanium shape memory alloy (Nitinol or NiTi) is a fascinating
material for dental applications. In this work the alloy has been produced by powder
metallurgy approach. The effect of Mg and Zn additives studied on the; hardness,
porosity percentage, and corrosion rate has been studied. Master Samples (without
additives) were prepared using powder mixture of 55 wt% Ni and 45 wt% Ti by
mixing them in a ball mill for two hours, then compacted at 300, 400, 500, 600, 700,
and 800 Mpa, then sintered at 950 oC for 9 hours under controlled atmosphere
(argon). The same approach was used for the prepared samples with Mg and Zn
additions compacted at 800 Mpa. XRD examination shows that the sintered samples
are consisting of two phases martensite and austenite at room temperatures, this mean
thermal NiTi shape memory alloy. From the results, it was found that Mg additives
increase hardness and decrease the corrosion rate while Zn additives increase the
corrosion rate.
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