Hafnium silk (pinyin: H. Descr [1]) is made of metal hafnium. Hafnium raw materials and products:

I. Zirconium metal: content; 1. Spot zirconium additive (zirconium chip cake, small pieces, pieces); 2, spot zirconium bulk material, zirconium raw material cake; 3. Spot zirconium ingots; 4. Spot zirconium plate; 5. Supply zirconium rod, plate, target and zirconium wire (spot diameter 2.0) according to customer's requirements.

Two, hafnium metal: content; 99.96% : 1. Spot crystalline hafnium rod; 2, spot hafnium wire; (diameter 1.5m)
 

General situation of

(1) Hafnium wire: 99.96%

Specifications; 1mm-3mm or according to customer requirements,

(2) zirconium chips; For various zirconium alloy additive (agent),

Zirconium content more than 99.60%, the price is lower than the same quality of zirconium sponge,

Quantity: Perennial supply.

(3) zirconium wire; Content; 99.60%, above.

Specifications; 1mm-6mm or supply according to customer requirements,
 

Refining process editing broadcast

The smelting of hafnium is basically the same as that of zirconium, generally in five steps. The first step is the decomposition of ore, there are three methods: Zircon chlorination to obtain (Zr,Hf)Cl4. (2) Alkali melting of zircon. When zircon and NaOH melt at about 600ºC, more than 90% (Zr,Hf)O2 changes to Na2(Zr,Hf)O3, and SiO2 changes to Na2SiO3, which is removed by aqueous solution. Na2(Zr,Hf)O3 can be used as the stock solution for zirconium and hafnium separation after being dissolved with HNO3, but it is difficult for solvent extraction separation due to the presence of SiO2 colloids.  K2(Zr,Hf)F6 solution was obtained after sintering with K2SiF6 and water immersion. Zirconium and hafnium can be separated by fractional crystallization in solution. The second step is the separation of zirconium and hafnium, which can be separated by solvent extraction of hydrochloric acid -MIBK (methyl isobutyl ketone) system and HNO3-TBP(tributyl phosphate) system. Multistage fractionation using the vapor pressure difference between HfCl4 and ZrCl4 melts at high pressure (above 20 atmospheres) has been studied for a long time, which can save the secondary chlorination process and reduce the cost. However, due to the corrosion of (Zr, Hf)Cl4 and HCl, it is difficult to find suitable fractionation column materials, and the quality of ZrCl4 and HfCl4 will be reduced, increasing the cost of purification. The third step is the secondary chlorination of HfO2 to produce crude HfCl4 for reduction. The fourth step is the purification and magnesium reduction of HfCl4. This process is the same as the purification and reduction of ZrCl4, and the semi-finished product is coarse sponge hafnium. The fifth step is vacuum distillation of coarse sponge hafnium to remove MgCl2 and recover excess magnesium metal, resulting in the finished product of sponge hafnium metal. If the reducing agent is sodium instead of magnesium, the fifth step is water immersion.

The sponge hafnium should be taken out of the crucible with extreme care to avoid spontaneous combustion. Large sponges of hafnium are broken into small pieces of a certain size so that they can be pressed into consumable electrodes and then fused and cast into ingots. Spontaneous combustion should also be prevented when broken. Sponge hafnium is further purified by iodide thermal decomposition as with titanium and zirconium. Control conditions are slightly different from zirconium, in the iodized tank around the sponge hafnium small block, maintain the temperature of 600ºC, and the center of the hot wire temperature of 1600ºC, than the zirconium "crystallization rod" when the high 1300ºC. The processing of hafnium includes forging, extrusion, tube drawing and other steps, as in the processing of zirconium.
 

use

The main use of hafnium is to make control rods for nuclear reactors [3]. Pure hafnium has plasticity, easy processing, high temperature resistance and corrosion resistance, is an important material in the atomic energy industry. Hafnium is an ideal neutron absorber with a large thermal neutron capture cross section, and can be used as control rods and protective devices in atomic reactors. Hafnium powder is used as a rocket booster. Cathodes for X-ray tubes can be manufactured in the electrical industry. Hafnium alloys can be used for rocket nozzles and leading edge protection for glider reentry vehicles, and Hf-Ta alloys can be used for tool steel and resistance materials. Hafnium is used as an additive element in heat-resistant alloys, such as those with tungsten, molybdenum, and tantalum. HfC can be used as carbide additive because of its high hardness and melting point. The melting point of 4TaC·HfC is about 4215ºC, which is the highest known compound.