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Niobium is a metal element. Chemical symbol Nb, atomic number 41, atomic weight 92.90638, belongs to the periodic system V B family. In 1801, C. Hatchet of England separated an oxide of a new element from niobium iron ore and named it columbium.

Basic uses: About 50% of tungsten ore mined in the world is used for smelting high-quality steel, about 35% for producing hard steel, about 10% for tungsten wire and about 5% for other uses.

Tantalum has a wide range of applications because of its characteristics. Tantalum can be used as a substitute for stainless steel in the equipment for making various inorganic acids, and its service life can be increased dozens of times than that of stainless steel.

Niobium is a metal element. Chemical symbol Nb, atomic number 41, atomic weight 92.90638, belongs to the periodic system V B family.

Smelting method: Ta-Nb ore is often accompanied by many metals. The main steps of Ta smelting are decomposing concentrate, purifying and separating Ta and Nb to produce purified compounds of Ta and Nb, and finally producing metal.

At present, titanium reactor can be divided into pure titanium reactor, composite titanium reactor and lining titanium reactor, which are used in different process environments. Composite titanium reactor is widely used because of its superior performance and lower price than pure titanium reactor.

Reference (related technology of National Standard GB/T3462-2007 Molybdenum Bar and Molybdenum Slab) Indicator name GMPM. 1 1 GMH [.M. 12 GMHYM. I.3

Titanium screw and nut are tools for tightening machine parts step by step, using the physical and mathematical principles of oblique circular rotation and friction of objects.