A method of measuring the magnetic susceptibility of 0·4 mm diameter stainless steel orthodontic wires is described. Experiments are reported, using the above technique, which show the variability of composition and structure which exists between samples of wire from different manufacturers. Additional results indicate the effect, on magnetic susceptibility, of work hardening as a result of bending and also heat treatment. Recommendations are made for the clinical use of the wires tested.
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References
1.
AbornR. H. and BainE. C. (1930) The nature of nickel-chromium rustless steels, Transactions of the American Society of Metals, 23, 225.
2.
British Standard 3507 (1962) Specification for orthodontic wire and tape and dental ligature wire made of stainless steel. London: British Standards Institution.
3.
CinaB. (1954) The effect of cold work on the γ to α transformation in some Fe-Ni-Cr alloys, Journal of The Iron and Steel Institute, 177, 406.
4.
CinaB. (1955) The metastability of austenite in an 18/8 Cr-Ni alloy, Journal of The Iron and Steel Institute, 179, 230.
5.
HozelitzK. (1944) The iron nickel phase diagram by magnetic analysis of the effect of cold work, Journal of The Iron and Steel Institute, 149, 193.
6.
RollasonE. C. (1961) Fundamental aspects of molybdenum on transformation of steel. London: Climax Molybdenum.
7.
SokolovN. V., BobylevaS. F., Rol'ShchikovL. D., AndrianovaA. L. (1966) Special features in the production of stainless steel spring wire. Stal (in English).
8.
SucksmithW. (1939) Magnetic saturation intensities at different temperatures, Proceedings of the Royal Society, Al70, 551.
9.
WilliamsD. W. (1974) The physical properties and microstructure of austenitic stainless steel orthodontic spring wire. Ph.D. Thesis, University of London. 206–208.
