Niobium carbide

CAS (12069-94-2

EINECS. 235-117-8

physico-chemical property

Niobium carbide is green cubic crystal with metallic luster and belongs to sodium chloride cubic crystal system.

Relative density 8.47, lattice constant A =0.447nm,

Melting point is 3500 ℃. Microhardness >23.5 Gpa(>2400 kg/mm2), harder than corundum. 338000 N/was elastic modulus, thermal expansion coefficient of 6.65 * 10 ^ (6)/K, the thermal conductivity of 14 w/(m K), generate heat - 140.7 kJ/mol, specific heat capacity of 36.8 J/(mol · K), the resistivity of 35 mu Ω · cm.

Insoluble in hot and cold hydrochloric acid, sulfuric acid, nitric acid, soluble in hot hydrofluoric acid and nitric acid mixed solution. Stable at 1000~1100℃ and rapidly oxidized to niobium pentoxide above 1100℃. Niobium carbide is easy to be fused into titanium carbide, zirconium carbide, tungsten carbide and other compounds, and together to form a homogeneous solid solution mixture. Melting point: 3500℃, density: 7.6g/cm (25℃)

use

As an additive of carbide hard alloy, it is a component of ternary and quaternary carbide solid solution, such as WC-NBC-C ternary system. Also can make purple artificial gem.

Polycarbides based on it, such as NBC-WC-C ternary systems, can be used as nozzle lining materials for aerospace applications

Niobium carbide (NbC) is a green cubic crystal with metallic luster and belongs to sodium chloride cubic crystal system. It is a kind of high melting point, high hardness material, widely used in refractory high temperature material and hard alloy additive.

As carbide additive, it is the component of ternary and quaternary carbide solid solution, such as WC-NBC-C ternary system. Also can make purple artificial gem.

Niobium carbide has good chemical stability and high temperature performance. Insoluble in hot and cold hydrochloric acid, sulfuric acid, nitric acid, soluble in hot hydrofluoric acid and nitric acid mixed solution; The mixture was fused into titanium carbide, zirconium carbide, tungsten carbide and other compounds, and the mixture was produced together. Stable at 1000-1100℃ and rapidly oxidized to niobium pentoxide above 1100℃. Generally, it is packed in plastic bottles or aluminum foil bags inside the carton.

(2) Product use: Application in composite materials:- duplex ceramic: as one of the raw material of duplex ceramic material, made of niobium carbide duplex ceramic materials with high hardness, high melting point, good chemical stability and electrical conductivity, is often used in wear-resistant parts, cemented carbide cutting tools and electrode areas: not only can be used as a cemented carbide grain growth inhibitor, but also with other carbides formed outside the WC and Co third dispersoid, significantly improve the carbide hot hardness and thermal shock resistance to pressure oxidation resistance abilityNiobium carbide with improve the hardness of alloy and improve the fracture toughness of the alloy, etc, so it can be used for the preparation of the cutting performance of cemented carbide cutting tool materials and niobium carbide can be made into purple artificial gem - surfacing electrode, solid niobium carbide hard phase into the hardfacing layer organization, make the welding layer has good wear-resistant skeleton, wearability greatly improve the overlaying welding electrode wear-resistant alloy, its wear resistance than that of quenched 45 # steel (HRC50) 1.2 1.8 times as high, than in Fe - Cr - C - B running-in exceeds 2.4 to 3.6 times the resistanceWelds at the same time, wear-resistant overlaying welding layer without preheating, available in workpiece surface welding, surface tiny cracks can release of surfacing welding layer stress and not spreading within the parent metal and steel strengthening phase in the process of steelmaking trace niobium carbide, can achieve the effect of precipitation strengthening and fine grain strengthening, so as to improve the comprehensive mechanical properties of steel, aerospace parts: used for turbine rotor blade engine nozzle jet vane lining and nuclear reactor structure and many other aviation equipment spare parts preparation of materials in the application of coating materials:- die steel surface coating: niobium carbide as metal carbides, has the very high hardness heat strength and abrasion resistance so it applied in steel shows that can improve the die surface wear resistance - metal work-piece coating: in the metal matrix composite niobium carbide surface of workpiece, make its surface hardness is greatly increased, can achieve HV2800 above, at the same time, improve the working temperature of the workpiece density and organization, so as to extend its service life by chemical liquid phase deposition process can realize the niobium carbide coating in the surface of cast iron piston rings, coating and the base material in combination with the strong;This coating piston ring has good storage pocket shape structure, and the advantages of both high hardness, can be significantly reduced without lubrication medium and the sliding friction coefficient when the diesel engine oil lubrication, greatly improving the wear resistance, can reduce the friction loss of diesel engine at the same time, improve diesel engine performance - other niobium carbide coating: spacecraft of high temperature components using niobium carbide coating, can make its service life significantly improved in the electronic industry, electronic tubes intermediary material using ultrafine cobalt containing niobium carbide, to improve the rate of radiation on the surface of the gridLower the temperature in the grid and reduce the grid thermal emission have a significant effect, so as to prolong the life of electronic tubes in the application of metal niobium production: the main indirect reduction method is used to produce metal niobium, the output of niobium carbide first used as a reductant, and niobium pentoxide generated thick metal niobium, made for refining high purity metal niobium addition, niobium carbide can also direct reduction to generate pure metal niobium niobium pentoxide.