Nitinol History

Scientists have been testing and testing SMA since 1932, but the material was not removed from the laboratory until 1962. William Beuhler works at the US Naval Research Laboratory and has discovered the SMA effect of nickel and titanium alloy. At that time, the science team was trying to develop an alloy that is resistant to heat and corrosion. In the production of corrosion-resistant alloys, they have made shape memory alloys (SMA) made from 55% nickel and 45% titanium. This new material is relatively cheap and safe (non-toxic) than previous SMA.

The team called their new alloy Nitinol (all in one overnight). The name represents its element composition and origin. "Ni" and "Ti" are atomic symbols for nickel and titanium. "NOL" stands for the discovered Naval Regulations Laboratory.

Although the mixture of nickel and titanium in the nickel-titanium alloy is substantially equal, the minimal change in the ratio of the two compounds has a large effect on the transition temperature of the resulting alloy. For example, a proportional difference of 1% will change the transition temperature from -100 to + 100 ° C. Every company that manufactures nitinol products today must maintain an accurate level of composition to ensure a stable and reproducible transition temperature. The transition temperature of nitinol we are testing is 70 ° C.

For medical applications (Nitinol # 1, Nitinol # 2, Nitinol # 4 and Nitinol # 8) and Nitinol # 5, Nitinol # 6 and Nitinol # 9, Fort Wayne Metals are suitable for a variety of other uses. All grades of Nitinol can be heat treated as cold working (CW) conditions or as superelastic (SE) wire extending straight. Fort Wayne Metals has developed a new technology that provides unique mechanical properties called Nitinol called Dynamic Plateau Strength (DPS). This process is also possible. If you need a particularly smooth surface, we recommend using SilkTM Nitinol Wire. This achieves a surface texture of 3 μin RMS without mechanical or electrolytic polishing.

Heat treatment nitinol is subtle and important. Fine tuning the transition temperature is a knowledge intensive process. The aging time and temperature control the precipitation of various nickel-rich phases to control the nickel content in the NiTi lattice. The aging increases the transition temperature by exhausting the nickel matrix. A combination of heat treatment and cold working is important to control the properties of Nitinol products. Fatigue failure of Nitinol made equipment is subject to discussion. It is an optimum material for applications requiring great flexibility and motion (eg peripheral stents, heart valves, smart thermo-mechanical actuators, and electromechanical microactuators) and therefore must be larger than other metals. Fatigue strain