Нитрид титана

Химические свойства

gold or brown powder

Физические свойства

Bronze powder. Transition temperature 4.2 K. Corrosion resistant to molten metals such as Al, Pb, Mg, Zn, Cd, and Bi. Corroded by molten Na, Rb, Ti, V, Cr, Mn, Sn, Ni, Cu, Fe, and Co. Dissolved by boiling aqua regia, decomposed by boiling alkalis evolving NH₃.

Использование

Titanium nitride (TiN) is an extremely hard ceramic material, often used as a coating on Ti alloys, steel, carbide and Al components to improve the substrate’s surface properties. Applied as a thin coating (less than 5 μm), TiN is used to harden and protect cutting and sliding surfaces, for decorative purposes due to its gold appearance and as a non-toxic exterior for medical implants.

Угроза здоровью

Inhalation breathing in, oral eating or drinking, or dermal exposure skin contact to some organotin compounds has been shown to cause harmful effects in humans, but the main effect will depend on the particular organotin compound. There have been reports of skin and eye irritation, respiratory irritation, gastrointestinal effects, and neurological problems in humans exposed for a short period of time to high amounts of certain organotin compounds. Some neurological problems have persisted for years after the poisoning occurred. Lethal cases have been reported following ingestion of very high amounts. Studies in animals have shown that certain organotins mainly affect the immune system, but a different type primarily affects the nervous system. Yet, there are some organotins that exhibit very low toxicity. Exposure of pregnant rats and mice to some organotin compounds has reduced fertility and caused stillbirth, but scientists are still not sure whether this occurs only with doses that are also toxic to the mother. Some animal studies also suggest that the reproductive organs of males may be affected

Промышленное использование

Titanium nitride, TiN, is a light-brown powderwith a cubic lattice crystal structure. Sinteredbars are extremely hard and brittle, with a hardnessabove Mohs 9 and a melting point of2950°C. It is not attacked by nitric, sulfuric, orhydrochloric acid, and is resistant to oxidationat high temperatures. In recent years, titaniumnitridecoatings have been used to markedlyextend the life of tool-steel cutters and formingtools. The coatings, golden in color, are depositedby chemical or physical vapor deposition.Aluminum nitride, AlN, when molded intoshapes and sintered, forms a dense, nonporousstructure with a hardness of Mohs 6. It resiststhe action of molten iron or silicon to 1704°C,and molten aluminum to 1427°C, but isattacked by oxygen and carbon dioxide at760°C. At least 1% oxygen causes AlN propertiesto deteriorate rapidly.