Niobium carbide is a green cubic crystal with metallic luster and belongs to the sodium chloride type cubic crystal system. Niobium carbide is a metal carbide with the chemical formula NbC.
Characteristics of Niobium Carbide:
The melting point of niobium carbide is 3500 ℃, and its microhardness is> 23.5 Gpa (> 2400 kg / mm2), which is harder than corundum. Niobium carbide has an elastic modulus of 338000 N / mm2, a thermal expansion coefficient of 6.65 × 10 ^ (-6) / K, a thermal conductivity of 14 w / (m · K), and a resistivity of 35 μΩ · cm.
Niobium carbide is insoluble in cold and hot hydrochloric acid, sulfuric acid, and nitric acid, and it is soluble in hot hydrofluoric acid and nitric acid mixed solution. It is stable at 1000 ~ 1100 ℃, and quickly oxidizes to niobium pentoxide above 1100 ℃. Niobium carbide is fusible in compounds such as titanium carbide, zirconium carbide, and tungsten carbide, and together forms a homogeneous solid solution mixture.
Fields of NbC Application:
1.NbC application in composite materials
(1) Composite ceramics
As one of the raw materials of multiphase ceramic materials, the manufactured multiphase ceramic materials are often used in the fields of wear-resistant parts, cutting tools and electrodes due to their high hardness, high melting point, excellent chemical stability, and conductivity.
(2) Hard alloy
Not only can be used as an inhibitor of cemented carbide grain growth but also can form a third dispersed phase with the exception of WC and Co together with other carbides, which can significantly improve the thermal hardness and resistance to thermal shock Antioxidant ability. Because niobium carbide has the advantages of improving the hardness of the alloy and improving the fracture toughness of the alloy, it can be used to prepare hard alloy cutting tool materials with excellent cutting performance.
(3) Surfacing electrode
The hard niobium carbide hard phase enters the structure of the surfacing layer, so that the welding layer has a better wear-resistant skeleton, and the wear resistance is greatly improved. The wear resistance of this electrode surfacing is 1.2 ~ 1.8 times higher than that of quenched 45 steel (HRC50), and 2.4 ~ 3.6 times higher than Fe-Cr-C-B type wear-resistant alloy.
(4) Aerospace components
It is used as preparation material for parts of many aerospace equipments such as turbine rotors, gas rudders, blades, engine nozzle linings, and structural parts of nuclear reactors.
2. NbC application in coating materials
(1) Mold steel surface coating
As a metal carbide, niobium carbide has high hardness, heat resistance, and abrasion resistance. Therefore, coating it on steel shows that it can improve the wear resistance of the mold surface.
(2) Coating of metal workpieces
The niobium carbide layer is compounded on the surface of the base of the metal workpiece, which greatly improves the surface hardness, which can reach HV2800 or higher, and at the same time, increases the working temperature and tissue density of the workpiece, thereby extending its service life.
(3) other niobium carbide coatings
The high-temperature parts of the spacecraft are coated with niobium carbide, which can significantly increase their service life. In the electronics industry, the material of the middle layer of the electron emission tube uses ultra-fine cobalt-containing niobium carbide, which has a significant effect on increasing the emissivity of the gate surface, reducing the gate temperature and reducing the thermal emission of the gate, thereby extending the electron emission tube's life.
3. NbC application in the production of metal niobium
Our country mainly uses indirect reduction to produce metallic niobium. The produced niobium carbide is used as a reducing agent, which interacts with niobium pentoxide to produce crude metallic niobium, and then is refined to obtain metallic niobium with higher purity. Besides, niobium carbide can directly reduce niobium pentoxide to form pure metal niobium.
TRUNNANO (Luoyang Trunnano Tech Co., Ltd ) is a professional Niobium carbide manufacturer with over 12 years experience in chemical products research and development. If you are looking for high quality Niobium carbide, please feel free to contact us and send an inquiry.
