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| | NIOBIUM BORIDE Basic information |
| | NIOBIUM BORIDE Chemical Properties |
| Melting point | 2270°C | | density | 7.500 | | form | gray orthorhombic crystals | | color | gray orthorhombic crystals, crystalline | | Resistivity | 40–64.5 (ρ/μΩ.cm) | | Thermal Conductivity | 16.736 W/(m·K) | | Crystal Structure | Orthorhombic | | CAS DataBase Reference | 12045-19-1 | | EPA Substance Registry System | Niobium boride (NbB) (12045-19-1) |
| Hazard Codes | Xi | | Risk Statements | 36/37 | | Safety Statements | 26-36 | | WGK Germany | 3 | | TSCA | TSCA listed |
| | NIOBIUM BORIDE Usage And Synthesis |
| Chemical Properties | gray powder(s); ortho-rhomb, a=0.3298 nm, b=0.872 nm, c=0.3166nm; resistivity 64.5μοhm· cm at 25°C; refractory material; commonly prepared by hot-pressing boron with niobium or niobium hydride; used as sputtering target with 99.5% purity to produce wear-resistant and semiconductor films, and can provide neutron absorbing layers on nuclear fuel pellets [KIR78] [KIR81] [CER91] [ALF93] | | Physical properties | Wear-resistant ; Major uses: semiconductive films,
neutron-absorbing layer on
nuclear fuel pellets | | Synthesis | 1, raw material preparation
The first step: niobium oxide powder with a particle size of 0.1μm, 3μm boron carbide powder and 3μm B2O3 powder were mixed uniformly in the ratio of 70:14:3 to obtain raw material powder 1.
Step 2: Mix the above raw material powder 1 with phenolic resin in the ratio of 5:0.5 by weight in a mixing mill, cure at a temperature of 80C, and then pulverize in a pulverizer to make raw material powder 2 with an average particle size of 10μm.
Step 3: Mix the above raw material powder 2 with phenolic resin in the proportion of 5:1 by weight in the mixing mill, curing at a temperature of 50, and then pulverized in the pulverizer to make the raw material powder 3 with an average particle size of 20μm.
Step 4: Mix the above raw material powder 3 with phenolic resin in the proportion of 5:2 by weight in the mixing mill, curing at a temperature of 40 , and then pulverized in the pulverizer to make an average particle size of 50μm raw material powder 4.
2. Synthesis of niobium boride powder
The above raw material powder 4 was briquetted under the pressure of 0.5Mpa, and then fired under argon atmosphere at the temperature of 1350C for 6 hours to produce niobium boride block.
3. Decarburization
The above niobium boride block is decarburized by holding it in oxidizing atmosphere at a temperature of 350C for 12 hours, and then crushed after cooling to produce niobium boride powder.
The purity of the raw materials used were 99.99% pure.
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| | NIOBIUM BORIDE Preparation Products And Raw materials |
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