Original scientific paper

Microstructure of NiTi orthodontic wires observations using transmission electron microscopy

J. Ferčec ; University of Maribor, Faculty of Mechanical Engineering, Maribor, Slovenia
D. Jenko ; Institute of Metals and Technology, Ljubljana, Slovenia
B. Buchmeister ; University of Maribor, Faculty of Mechanical Engineering, Maribor, Slovenia
F. Rojko ; University of Ljubljana, Faculty of Health Sciences, Ljubljana, Slovenia
B. Budič ; National Chemistry Institute, Ljubljana, Slovenia
B. Kosec ; University of Ljubljana, Faculty of Natural Sciences and Engineering, Ljubljana, Slovenia
R. Rudolf ; University of Maribor, Faculty of Mechanical Engineering, Maribor and Zlatarna Celje d.d., Celje, Slovenia

Abstract

This work presents the results of the microstructure observation of six different types of NiTi orthodontic wires by using Transmission Electron Microscopy (TEM). Within these analyses the chemical compositions of each wire were observed in different places by applying the EDS detector. Namely, the chemical composition in the orthodontic wires is very important because it shows the dependence between the phase temperatures and mechanical properties. Microstructure observations showed that orthodontic wires consist of nano-sized grains containing precipitates of Ti₂Ni and/or TiC. The first precipitated Ti₂Ni are rich in Ti, while the precipitated TiC is rich in C. Further investigation showed that there was a difference in average grain size in the NiTi matrix. The sizes of grains in orthodontic wires are in the range from approximately 50 to 160 nm and the sizes of precipitate are in the range from 0,3 μm to 5 μm.

Keywords

NiTi orthodontic wire; microstructure; TEM; EDS; average grain size

Hrčak ID:

122165

URI

https://hrcak.srce.hr/122165

Publication date:

1.10.2014.

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