Name | Vanadium carbide |
Synonyms | Einecs 235-122-5 VANADIUM CARBIDE Vanadium carbide methylidynevanadium Vanadium monocarbide vanadium(iv) carbide Vanadium carbide (VC) Vanadiumcarbide(metalsbasis) VANADIUM CARBIDE, POWDER, 1.5 TO 2 MICRO N VANADIUM CARBIDE HV 160 - A PRODUCT OF H.C.STARCK |
CAS | 12070-10-9 11130-21-5 |
EINECS | 235-122-5 |
InChI | InChI=1/CH.V/h1H;/rCHV/c1-2/h1H |
Molecular Formula | CV |
Molar Mass | 62.95 |
Density | 5.77g/mLat 25°C(lit.) |
Melting Point | 2810°C |
Boling Point | 3900℃ [KIR83] |
Water Solubility | Insoluble in water. |
Appearance | powder |
Specific Gravity | 5.77 |
Color | Black |
Exposure Limit | NIOSH: TWA 1 mg/m3; STEL 3 mg/m3; Ceiling 0.05 mg/m3 |
Storage Condition | 2-8℃ |
MDL | MFCD00049698 |
Physical and Chemical Properties | Black cubic crystals. It contains 19.08% carbon and belongs to the cubic system of sodium chloride. The melting point is 2810 ℃, the boiling point is 3900 ℃, and the relative density is 5.77. Soluble in nitric acid, insoluble in cold water, hydrochloric acid and sulfuric acid. Can be fused with potassium nitrate. The chemical properties are stable and resistant to chemical corrosion. This information was compiled by Ding Hong. (2015-09-09) |
Hazard Symbols | Xn - Harmful |
Risk Codes | 20/21/22 - Harmful by inhalation, in contact with skin and if swallowed. |
Safety Description | 36 - Wear suitable protective clothing. |
UN IDs | UN3178 |
WGK Germany | 3 |
TSCA | Yes |
Hazard Class | 4.1 |
Packing Group | III |
black-gray powder. The structure of the sodium chloride type cubic crystal system, the lattice constant a 0.4182nm. Relative density 5. 77; Melting point 2810 ℃; Boiling point 3900 ℃. The coefficient of thermal expansion is 7.2 x 10-6 /K and the resistivity is 150u.cm at room temperature. Insoluble in water, soluble in nitric acid and decomposition. Good chemical stability, high temperature performance.
The carbon powder and vanadium pentoxide are thoroughly mixed and reduced at a temperature above 1300 ° C. Under high vacuum to obtain Vanadium carbide.
It can be used as grain refiner in Cemented carbide, cutting tools and steel-making industry, and can obviously improve the properties of the alloy.
crystal structure | Cubic, NaCl Structure |
EPA chemical information | Information provided by: ofmpub.epa.gov (external link) |
application | vanadium carbide has the general characteristics of transition metal carbides such as high hardness, melting point and high temperature strength, and has good electrical and thermal conductivity. Therefore, it has a wide range of applications in the fields of iron and steel metallurgy, hard alloys, electronic products, catalysts and high-temperature coating materials. Among them, the addition of vanadium carbide in steel can improve the comprehensive properties of steel such as wear resistance, corrosion resistance, toughness, strength, ductility, hardness and thermal fatigue resistance, and can be used as a wear-resistant material in different cutting and wear-resistant Used in tools. In addition, due to its high activity, selectivity, stability and ability to resist "catalyst poisoning" in hydrocarbon reactions, vanadium carbide has also been widely used as a new type of catalyst. In addition, vanadium carbide can also be used as a new carbon source to synthesize diamond. The most important role of vanadium carbide is to be used as a grain inhibitor in the field of cemented carbide and cermet, which can effectively prevent the growth of WC grains in the sintering process. 1. Used for smelting high-strength low-alloy steel, pipeline steel and other steel grades. 2. Used in the production of cemented carbide and cermet. 3. As a raw material for extracting metal pure vanadium. |
overview | vanadium carbide, black cubic crystal, containing carbon 19.08%, belongs to sodium chloride cubic crystal system, gray metallic powder. Insoluble in water, sulfuric acid and hydrochloric acid, soluble in nitric acid, and soluble in molten potassium nitrate. It has excellent physical and chemical properties, such as high melting point, good electrical conductivity, good chemical resistance, etc.; it can be used as an important additive in cemented carbide and titanium-based cermets (the added mass fraction is less than 1%), Thereby inhibiting the grain growth in the process of carbide particle dissolution and precipitation; it can be used to smelt high-strength low-alloy steel, pipeline steel and other steel grades, so as to improve the wear resistance, corrosion resistance, toughness, strength, ductility, hardness and fatigue resistance of the steel, and make the steel have strong weldability, and can play a role in eliminating inclusions; At the same time, it can also be used as a raw material for extracting pure metal vanadium. |
preparation method | 1. vanadium pentoxide is used as raw material and carbon black is used as reducing agent. The total chemical reaction formula is: V2O5 7C = 2VC 5CO ↑ in fact, the reaction is carried out step by step: V2O5 C = 2VO2 CO ↑ 2VO2 C = V2O3 CO ↑ V2O3 C = 2VO CO ↑ VO C = V CO ↑ V C = VC fig. 1 is the process flow for VC production 2. carbothermic reduction method: ammonium metavanadate, graphite and titanium powder are used as raw materials, ammonium metavanadate and titanium powder are mixed evenly in a drum mixer with different contents of graphite at a material ratio of 1:1. Weigh uniformly mixed raw materials and press into a columnar compact with a diameter of 2 cm, place it in a graphite crucible, and carry out reduction carbonization in a vacuum sintering furnace. 3. Vacuum carbothermal reduction method: V2O3 is used as raw material, and the reaction of preparing vanadium carbide by carbothermal reduction method is: V2O3(s) 5C(s)= 2VC(s) 3CO(g). The operation method is: the reactants are screened by standard sieve and classification in advance, then the ingredients are measured according to the chemical reaction ratio, the carbon content is appropriately adjusted, additives and binders are added at the same time, and the reactants are fully mixed and pressed and formed, after drying at 150 ℃ for 24 h, it is placed in a vacuum carbon tube furnace with a temperature range of 1400~1800 K, a reaction time of 12~60 h, a vacuum degree of 6 × 10-2Pa, and then cooled to room temperature after reaction. 4. Using polyvanadate as raw material and carbon powder as reducing agent, vanadium carbide is prepared under nitrogen protection (normal pressure). The polyvanadate money has the following decomposition reaction during heating:>670 ℃: the total reaction of V2O5 = V2O4 1/2O2 carbon reduction to generate vanadium carbide can be expressed by the following formula: V2O5 6C = V2C 5CO ↑ the operation steps are: firstly, the polyvanadate money is dried in a drying oven at constant temperature for 4-8h, and the ground carbon powder is added into a conical rod mill for 15-20min, then add dextrin solution, stir evenly, press and form on a self-made briquetting machine, and then dry at a constant temperature of 105 ℃ for 4~8h for later use. The dried block material is put into a self-made shaft furnace, the temperature is raised to 1200~1550 ℃, the temperature is constant for 3~9 h, and hydrogen protection is introduced at the same time, and the hydrogen flow rate is 0.5 ~ 5L/ min. Naturally, they came out of the oven and got vanadium carbide products. |