Preparation and application of niobium boride powder

Overview of Niobium Boride NbB2 Powder

The chemical formula of niobium boride is NbB2 and the molecular weight is 114.528. It is a gray-black powder, niobium boride (NbB2) has the characteristics of high melting point, high hardness, good electrical and thermal conductivity, corrosion resistance to molten metal, superconductivity, etc., and can be used to produce ultra-high temperature structural materials And superconducting materials have important applications in extreme environments such as ultra-high temperature and metal smelting. Niobium diboride (NbB2) is a highly covalent refractory ceramic material with a hexagonal crystal structure.

NbB2 can be synthesized by a stoichiometric reaction between the constituent elements (in this case, Nb and B). This reaction allows precise stoichiometric control of the material. Nb2O5 (or NbO2) can also be reduced to niobium diboride by metal thermal reduction.

Preparation of Niobium Boride Powder

method one

CN201110136047.7 provides a reaction synthesis method of niobium boride powder with low cost and good sintering activity.

1. Raw material preparation:

The first step: uniformly mix niobium pentoxide powder with a particle size of 0.1 μm, 3 μm boron carbide powder and 3 μm B2O3 powder in a ratio of 70:14:3 to obtain raw material powder 1.

The second step: the above-mentioned raw material powder 1 and phenolic resin are mixed uniformly in a mixer at a weight ratio of 5:0.5, cured at a temperature of 80°C, and then crushed in a powder mill to obtain an average particle size of 10μm raw material powder 2.

The third step: the above-mentioned raw material powder 2 and phenolic resin are mixed uniformly in a mixer at a weight ratio of 5:1, cured at a temperature of 50°C, and then pulverized in a powder mill to obtain an average particle size of 20μm raw material powder 3.

The fourth step: the above-mentioned raw material powder 3 and phenolic resin are mixed uniformly in a mixer at a weight ratio of 5:2, cured at a temperature of 40°C, and then pulverized in a powder mill to obtain an average particle size of 50μm raw material powder 4.

2. Synthesis of niobium boride powder:

The raw material powder 4 was compacted under a pressure of 0.5Mpa, and then fired in an argon atmosphere at a temperature of 1350°C for 6 hours to obtain a niobium boride block.

3. Decarbonization treatment

The niobium boride block is kept in an oxidizing atmosphere at a temperature of 350° C. for 12 hours to decarburize, and then pulverized to obtain a niobium boride powder after cooling.

The purity of the raw materials used is 99.99% pure.

Method Two

Nano-NbB2 powder has a higher reactivity than micron NbB2 powder due to its small particle size. The use of nano-NbB2 powder can effectively reduce the sintering temperature of the ceramic material, increase the density of the ceramic, and then improve the performance of the ceramic material. In addition, as a reinforcing phase, nano-powder has stronger toughness than micro-powder. Therefore, the synthesis of nano-NbB2 powder has great practical value.

Weigh 0.580g of Nb2O5, 0.173g of elemental B powder, 3.348g of NaCl, 4.271g of KCl, use ZrO2 balls as the ball milling medium, and mix them on a planetary ball mill for 1 hour; then put the mixed powder into the corundum crucible, Put it in a tube furnace, heat it to 1000°C under the protection of Ar gas and keep it for 1 hour, then cool to room temperature naturally. The above mixture was immersed in deionized water, heated to 80° C. and stirred for 0.5 h, and separated by vacuum filtration to obtain a precipitate. The precipitate was washed twice with deionized water at 80°C and washed once with ethanol, and dried at 60°C for 8 hours to obtain nano-NbB2 powder.

Application of niobium boride NbB2 powder

NbB2 is an ultra-high temperature ceramic (UHTC) with a melting point of 3050°C. Its relatively low density (about 6.97 g/cm3) and good high-temperature strength make it a candidate material for high-temperature aerospace applications (such as hypersonic flight) or rocket propulsion systems. Ceramic has high thermal conductivity and electrical conductivity (resistivity is 25.7ΩYbcm, Cte is 7.7 Yb10 -6°C-1), and has the same structure as NboB2, titanium diboride, zirconium diboride, and diboron Chemical ha and tantalum diboride have the same properties. Parts are usually hot pressed or spark plasma sintered (applying mechanical pressure to the heated powder) and then processed into shape. The covalent nature of NbB2 and the presence of surface oxides hinder the sintering of NbB2, thereby making the particles coarser and then dense during the sintering process. By using sintering additives such as boron carbide and carbon, NbB2 can be sintered without pressure. These sintering additives react with surface oxides to increase the sintering force, but the mechanical properties of NbB2 decrease compared with hot press sintering.

Niobium Boride NbB2 powder price

The price of niobium boride NbB2 powder varies randomly with factors such as the production cost, transportation cost, international conditions, exchange rate, market supply and demand of niobium boride NbB2 powder. Tanki New Materials Co.,Ltd. aims to help various industries and chemical wholesalers find high-quality, low-cost nanomaterials and chemicals by providing a full set of customized services. If you are looking for niobium boride NbB2 powder, please feel free to contact us for the latest price of niobium boride NbB2 powder.

Niobium Boride NbB2 Powder Supplier

As a global supplier of niobium boride NbB2 powder, Tanki New Materials has extensive experience in advanced engineering material properties, applications, and cost-effective manufacturing. The company has successfully developed a series of boride powder materials (including niobium boride NbB2 powder, molybdenum boride, tungsten boride, etc.), high-purity targets, functional ceramics, structural devices, and provide OEM services.