Nitinol sma is an amazing metal that not only has shape memory properties, but is also super elastic. Nickel titanium alloy root canal files use the super elasticity for canal file treatment. Why the performance of Nitinol sma root canal files is so good is inseparable from some processing details. That is, vacuum heat treatment is required, and only the root canal file that has undergone heat treatment can achieve the best performance, and the overall performance of primary color vacuum heat treatment is excellent. And there are other colors, such as, blue, gold, coloring does not need to add other extra chemicals, only need to pass gas to obtain.

What is the meaning of vacuum heat treatment?

First of all, when the workpiece is heated in a vacuum furnace, under a negative pressure environment, there are few oxidizing and decarburizing components, and the partial pressure of oxidizing gas in the atmosphere is much lower than the oxygen decomposition pressure of iron, carbon and alloying elements in the parts. . Therefore, the workpiece will not be oxidized and decarburized during the vacuum heat treatment process, which greatly improves the service life of the workpiece;

Secondly, the distortion of the workpiece is small, the temperature rises slowly in the low temperature stage of vacuum heating, the temperature difference at the core of the workpiece surface is extremely small, and the temperature distribution in the vacuum furnace is uniform, and the temperature difference in the furnace is less than 5 degrees Celsius, so the heating deformation of the workpiece is very small;

Finally, vacuum heating has the effect of degreasing and degassing. Oil impurities such as lubricating oil and emulsion are mainly carbon, hydrogen and oxygen compounds, which can be decomposed into water vapor, carbon dioxide, hydrogen and other gases when heated. Evaporate and be extracted by the vacuum pump (the vacuum pump will not be burned out, there are three reasons: the vacuum system is equipped with a water-cooled circulation device, 2. The furnace is equipped with a heat shield, which plays a role in heat preservation and insulation, 3. The heating element is in the working area of ​​the furnace, and the high temperature reaches without a vacuum pump) so a smooth metal surface can be obtained. In addition, heating in vacuum can promote the diffusion of various gases dissolved in the metal to the surface, so that harmful gases are released and discharged to the outside of the furnace, which plays a role in degassing, thereby improving the quality of the workpiece.

How about heat treatment?

The first step is to put the nitinol workpiece into the ultrasonic container, and clean the surface of the root canal file to ensure that the surface is free of oil stains;

The second step is to put the workpiece into the furnace of the vacuum heat treatment equipment. According to the process requirements, two methods of rapid cooling and ordinary cooling are selected respectively;

The third step is to set the temperature required for heating, the holding time, and select automatic operation;

The treated nickel-titanium alloy root canal file has strong flexibility, cyclic fatigue resistance, lower torque and bending resistance, increased cutting efficiency and wear resistance, is not easy to break, and increases efficiency and wear resistance. These properties make the NiTi file less offset during root canal treatment, less prone to lateral penetration, and reduce the risk of instrument separation.