1. Coating Field

TiN coatings are among the earliest studied and most market-dominant nitride coatings. They find wide application on cutting tools, bearings, and molds to extend service life and reduce economic losses. For instance, compared with uncoated tools, TiN-coated ones boost cutting speed by 25%~70%, improve machining accuracy by 0.5~1 grade, cut tool consumption costs by 20%~50%, enhance wear resistance 2~10 times, and greatly prolong service life. Clearly, TiN coatings play a significant role in promoting industrial production.

2. Biomedical Field

TiN boasts excellent biocompatibility, making it suitable for clinical medicine and bionics. The internal environment of organisms is highly complex. Traditional medical metal materials tend to degrade functionally under such conditions, and in severe cases, the deteriorated materials may harm the organism. Depositing a TiN ceramic coating on the surface of medical metals effectively enhances their corrosion resistance and biocompatibility. Researchers have prepared TiN/Ti composites via ion plating technology and tested them in animals. The results show these composites offer better adaptability and biocompatibility than pure titanium and medical stainless steel. In stomatology, TiN is mainly used as a surface coating for cutting tools, implants, and dentures. It forms a protective oxide layer that slows corrosion of implants in the oral electrolyte environment and extends the service life of medical devices.

3. Microelectronics Field

In the microelectronics field, TiN’s excellent electrical conductivity makes it ideal for semiconductor device electrodes, buffer layers, and barrier layers. For silicon-based integrated circuits, copper (Cu) has become the most advantageous wiring material due to its low resistivity and excellent electromigration resistance. However, Cu easily diffuses into silicon and its compound substrates, severely affecting semiconductor performance. To address this issue, a thin TiN layer—with low resistivity and good thermal stability—is inserted between the Cu film and the substrate, acting as a TiN barrier layer. This layer not only blocks Cu diffusion but also improves the adhesion strength of the Cu film. It has been widely adopted in integrated circuits: Cu/TiN/Si multilayers with a 40nm TiN coating still maintain high barrier efficiency after heat treatment at 575°C for two hours.

4. Coating Decoration Field

As living standards improve, simple and practical decorative materials can no longer meet people’s growing spiritual needs. The gold-like luster has a special appeal, prompting substantial investment in the gold imitation field. Unlike traditional Cu-based gold imitation alloys or chemical gold plating— which are costly, environmentally harmful, and unsustainable—TiN films have optical properties similar to precious metals like gold and silver. They are also non-toxic and affordable, making them an ideal choice for modern gold imitation materials. Researchers have prepared TiN films via magnetron sputtering and explored the impact of nitrogen content on film color. The results show that as the N/Ti ratio increases, the film’s color undergoes various changes. This controllable color variability gives TiN films broad prospects in the decoration and jewelry industries.

5. Other Fields

TiN films are translucent in the visible light region and highly reflective in the infrared region, opening up promising applications in smart glass. TiN has a higher melting point than most transition metal nitrides but a lower density— a unique combination that makes it suitable for refractory materials. Advances in modern material preparation technology have expanded TiN’s applications to areas such as energy storage, batteries, and detectors. With simple preparation and excellent performance, TiN has become an indispensable material in modern industrial production.