A Safety Device Based on a High Temperature Shape Memory Alloy

A device has been developed based on alloys with a high-temperature shape memory effect. It aims to be used in mechanical engineering products, in particular, nuclear technology, in order to prevent emergency situations of man-made and natural nature. The device works by breaking the electrical circuit in the event of an emergency increase in the ambient temperature above the permissible temperature by cutting the electrical cable. The shape restoration properties of thermosensitive working elements made of the Ni 49.5 Ti 48.0 Hf 2.5 alloy with high temperature shape memory have been studied. The results of the experiments allow us to conclude that it is possible to use the device in electrical systems for cutting heat-resistant electrical cables with an outer diameter of d out = 3.4–5.0 mm and a copper wire cross-section of 0.2–1.5 mm 2 with a knife in an emergency situation, when the ambient temperature exceeds 100°С and the maximum heating reaches 200°С.