high purity Niobium crucibles rare metal size customizable outlet

NB crucible 99.95% Introduction

The Nb crucible can be customized according to the different needs of customers, and the specification and dimensional tolerance can be negotiate.

Niobium is a gray white metal with a melting point of 2468 ℃, a boiling point of 4742 ℃, and a density of 8.57 g / cm3. Niobium is stable in air at room temperature, and is not completely oxidized when it is red hot in oxygen. At high temperature, niobium is directly combined with sulfur, nitrogen and carbon to form alloys with titanium, zirconium, hafnium and tungsten. It does not react with inorganic acids or bases,but soluble in hydrofluoric acid. Niobium is extremely stable in air at room temperature and does not interact with air. Although it has a higher melting point (2468 ° C) in elemental state, its density is lower than that of other refractory metals. Niobium can resist all kinds of erosion and form dielectric oxide layer.

The electronegativity of niobium is lower than that of zirconium on its left. The size of the atom is almost the same as that of tantalum under it, which is caused by the effect. This makes the chemical properties of niobium very similar to tantalum. Although its corrosion resistance is not as high as tantalum, its price is lower and it is more common. Therefore, it is often used to replace tantalum when the requirements are low, for example, as coating material in chemical tank of chemical plant .Crucible is an important part of chemical instrument. It is the container for melting and refining metal liquid, heating and reaction of solid and liquid, and is the basis of ensuring the smooth progress of chemical reaction. There are many types and specifications of crucible, which is not limited by production scale, batch size and melting material variety. It can be selected arbitrarily and has strong applicability, and can ensure the purity of the melted material.

Notice

1. After use, it should be placed in a dry place and should not be invaded by rain. Before use, it should be slowly baked to 500 ℃. 2. The material should be added according to the capacity of the crucible. It is not allowed to squeeze too tightly to prevent the metal from thermal expansion and cracking of the crucible. 3. When taking out the molten metal, * scoop it out with a spoon and use fewer calipers as far as possible. If calipers and other tools are used, they should be consistent with the shape of the crucible, so as to avoid shortening the service life due to excessive local stress. 4. The service life of the crucible is related to its usage. It should be avoided that the strong oxidation flame is directly sprayed on the crucible to make the raw materials of the crucible short-lived. There are three types of raw materials for crucible production. One is crystalline natural graphite, the other is plastic refractory clay, and the third is calcined hard kaolin skeleton clinker. Since 2008, high temperature resistant synthetic materials, such as alumina, Emery and ferrosilicon, have been used as the skeleton clinker of crucible. This kind of clinker has a significant effect on improving the quality of crucible products and enhancing the density and mechanical strength of crucible.