Titanium nitride (TiN), as a new type of multifunctional cermet material, has excellent characteristics such as high melting point, high hardness, wear resistance, good chemical stability, good electrical and thermal conductivity, and good optical performance. Its melting point is 2930 ~ 2950 ℃, it is a good conductor of heat and electricity, and it has superconductivity at low temperature. It is a material for manufacturing jet engines. With the development and breakthrough of science and technology, it plays a different role in many fields. The unique golden yellow metallic luster makes titanium nitride also have applications in the field of gold decoration.
(1) Application in tool manufacturing
The titanium yellow ceramic coating has a golden appearance. Although it has the advantage of optimizing the appearance of the tool, it is not used for decoration. It has a hardness value of 2500 or higher in the Vickers hardness (HV). The thickness of the coating on the tool is generally 3 to 5 microns, which has higher wear resistance and heat resistance and longer service life than the original product that has not been coated. Apply this technology to mechanical equipment in industrial production, such as coating titanium nitride on the gear hob, its life can be extended by 3 to 4 times, and the cutting speed or feed can be increased more when cutting gears. Thereby reducing material machining time. The utilization rate of coated high-speed tools in industrial developed countries has accounted for 70% of high-speed tools. Almost all of the automotive industry uses coated high-speed steel knives to process gears, and the rolling speed can reach 70 ~ 150m / ㎜.
In China, the major national science and technology project hosted by Professor Liu Ning of the School of Materials Science and Engineering of Hefei University of Technology in 2005 was to study nano-TiN and AlN modified titanium carbide-based cermet tools. The research shows that the TiC-based cermet cutter modified by nano-TiN has excellent mechanical properties and is a new kind of cutter with high technical content and high added value. At the same time, after more than 4 months of use by users, it has been shown that this tool can partially replace carbide tools such as YC8 and YT15 in the field of cutting processing. The tool life is more than doubled, and the production cost is comparable to or slightly lower than YC8 tools. This research has enabled the development of new cermet cutting tools made of nanomaterials in China, and it also marks the new progress of special ceramics research in China.
(2) Application in biomedicine
The occluder used to treat atrial septal defect, ventricular septal defect, and patent ductus arteriosus in congenital heart disease has been widely used in clinical medicine as an implant for interventional therapy. However, most of the conventional concentric occluders are made of nickel-titanium alloy materials, which contain nickel up to 55%, and excessive nickel can cause allergies and poisoning to the human body, and the long-term effect is more likely to induce cancer. The purifying membrane on the surface of the nickel-titanium alloy of the occluder can be destroyed. In the complex human body environment, the internal nickel ion release will increase the content of nickel, which will further deteriorate the tissue compatibility of the occluder.
Related research shows that because titanium nitride (TiN) is a biocompatible material (once used for coronary stents), thrombogenicity is much lower than nickel titanium itself. As early as 2004, Xianjian Technology (Shenzhen) Co., Ltd. developed a Cera ceramic membrane occluder using high-energy ion precipitation coating technology for this medical problem. Based on the design of the original nickel-titanium alloy occluder Maintain the design of the original room septal occlusion device, ventricular septal occlusion device, and arterial catheter occlusion device, using plasma technology to uniformly wrap a layer of titanium nitride TiN film on the surface of its nickel-titanium alloy, using ion technology to make the metal The combination of titanium coating and C, N, O, etc. is converted into a biological coating, which greatly improves the corrosion resistance of the occluder and the compatibility of biological tissue and blood. According to the comparison of animal experimental data from Cera ceramic membrane occluder and ordinary nickel-titanium occluder: Cera ceramic membrane occluder is far superior to ordinary nickel-titanium occluder in cell crawling growth performance. Improving the repair of congenital heart disease defects while significantly reducing the risk of thrombosis; platelet adhesion and hemolysis rate is also much lower than ordinary nickel-titanium occluder. At present, the Cera occluder has been approved by regions and countries including the European Union, India, Brazil, and Russia, and has been used in more than thousands of patients with congenital heart disease.
(3) Application of the film on the front block of the car
Nowadays, after buying a car, it seems that it has become a standard to attach a heat-insulating protective film to the car. The film in the main radiation area of the front windshield of the car is even more important. After all, the car film has a part that blocks ultraviolet rays and blocks. Heat and prevent injuries and glare caused by the sudden burst of glass, and reduce the damage caused by ultraviolet radiation in objects and people in the car. At present, there are many types of automobile heat insulation films on the market, which are different in material function, service life and effect presentation. Based on nano-titanium nitride, the combination of magnetron sputtering technology and metal nitriding technology produces a nano-ceramic film that is not only durable, not easy to corrode, but also has the advantage of not shielding mobile phone signals and good heat dissipation, product performance To a large extent, it is superior to other types of automotive insulation films. The earliest nano-ceramic insulation film is an amber optical nano-ceramic insulation film developed by German Shaohua Technology Company in 2001, which is used in marine, architectural and automotive glass films.
The difference between nano-ceramic insulation film and metal insulation film is as follows:
1. Sunscreen and heat insulation are different
The heat dissipation of the metal film is worse than that of the ceramic film, the heat insulation effect is general, and the reflection rate is higher. The ceramic membrane achieves the purpose of heat insulation through the selective filtering function of the solar spectrum. The heat insulation is far more than the metal, the reflection rate is lower, and the stability is excellent.
2. Different signal passing rates
A key difference between the metal film and the ceramic film is the barrier rate to the signal. The metal film has interference to the imported GPS, and it is also ETC (non-stop electronic toll collection system), which is easy to affect the passage of various signals. The metal film and the multi-layer metal film, although the multi-layer metal film is superior to the single-layer metal film in thermal insulation, but because of its deeper thickness, the signal shielding becomes more serious. The ceramic film will not shield the signal after removing the metal characteristics.
3. Different oxidative shelf life
The metal film is easy to oxidize and the shelf life is slightly shorter, while the chemical nature of the ceramic film is relatively stable, it is not easy to oxidize, and it is resistant to acid and alkali organic solvents, so that it can have a long service life. The shelf life of general ceramic thermal insulation film is 10 years, and that of metal thermal insulation film is 5 years.