NiTi spring coils were used to obtain large deformation under a constant force. The device consists on a NiTi coilspring, superelastic at body temperature, in order to have a stress plateau during the austenitic retransformationduring the unloading. The temperature variations induced changes in the spring force.Objectives: The aim of this study is to investigate the effect of the temperature variations in the spring forces andcorrosion behaviour simulating the ingestion hot/cold drinks and food.StudyDesign: The springs were subjected to a tensile force using universal testing machine MTS-Adamel (100 Nload cell). All tests were performed in artificial saliva maintained at different temperatures. The corrosion testswere performed according to the ISO-standard 10993-15:2000.Results: The increase in temperature of 18oC induced an increase in the spring force of 30%. However, when thetemperature returns to 37oC the distraction force recovers near the initial level. After cooling down the spring to15oC, the force decreased by 46%. This investigation show as the temperature increase, the corrosion potentialshifts towards negative values and the corrosion density is rising.Conclusions: The changes of the temperatures do not modify the superelastic behaviour of the NiTi closed-coilsprings. The corrosion potential of NiTi in artificial saliva is decreasing by the rise of the temperatures.
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