Hafnium is a chemical element; it has symbol Hf and atomic number 72. A lustrous, silvery gray, tetravalent transition metal, hafnium chemically resembles zirconium and is found in many zirconium minerals. Its existence was predicted by Dmitri Mendeleev in 1869, though it was not identified until 1922, by Dirk Coster and George de Hevesy.

Zircon is the primary source of all hafnium. Zirconium and hafnium are contained in zircon at a ratio of about 50 to 1. Zircon is a coproduct or byproduct of the mining and processing of heavy-mineral sands for the titanium minerals, ilmenite and rutile, or tin minerals.

2018年6月13日 · Hafnium is a ductile metal with a brilliant silver luster. It does not exist as a free element in nature; it is always associated with zirconium. Its existence was predicted as early as 1869 by Dmitri Mendeleev, but it wasn’t discovered until 1923 when it was found in the mineral zircon by X-ray spectroscopic analysis.

This table compares the known valid mineral species listed listed with Hafnium and the other elements listed based on the official IMA formula. Note that unlike other sections on this page this includes non-essential elements. The first data column contains the total number of minerals listed with Hafnium and the element listed for that row.

Hafnium is considered a "critical mineral" in domestic metallurgical applications that serve aerospace, defense, and energy technologies (Fortier and others, 2018). Due to its striking similarities to the element zirconium, hafnium was not recognized as its own element until 1923. It is difficult to separate from zirconium.

Hafnium, chemical element, metal of Group 4 (IVb) of the periodic table. It is a ductile metal with a brilliant silvery luster. It is dispersed in Earth’s crust to the extent of three parts per million and is invariably found in zirconium minerals up to a few percent compared with zirconium.

2019年9月29日 · Hafnium is a shiny, silvery, ductile metal that is corrosion resistant and chemically comparable to zirconium (since it has the same number of valence electrons, being in the same group, but also to relativistic effects; the expected expansion of atomic radii from period 5~6 is practically canceled out by the lanthanide contraction) (Table 7.10).

Hafnium is a metallic element that occurs especially in zirconium minerals and is used in control rods for nuclear reactors

2017年12月19日 · Zirconium and hafnium are corrosion-resistant metals that are widely used in the chemical and nuclear industries. Most zirconium is consumed in the form of the main ore mineral zircon (ZrSiO4, or as zirconium oxide or other zirconium chemicals.

Hafnium is an unreactive metal, unaffected by air, water, most acids or bases. Like cadmium, it absorbs neutrons, and consequently is used in the control rods of nuclear reactors, especially reactors found on nuclear submarines. It is also used in …