Manufacturing Process of Tungsten Bar

Tungsten exhibits a body-centred cubic (bcc) crystal lattice. It has the highest melting point of all metals, 3,410° C (6,170° F), and it has high conductivity for electricity. Owing to this unique combination of properties, it is used extensively as filaments for incandescent lamps, as electric contacts, and as electron emitters for electronic devices. Tungsten also has found wide application as an alloying element for tool steels and wear-resistant alloys. Tungsten carbides are used for cutting tools and hard-facing materials owing to their hardness and resistance to wear. The metal is brittle at room temperature but ductile and strong at elevated temperatures. Its alloys are employed in rocket-engine nozzles and other aerospace applications.  

The process of making tungsten bar is not complex and diffcult. Tungsten suppliers produce tungsten bars by grinding tungsten metal ore into a fine powder. Chemical processing of the powder then forms tungsten oxide, which is heated to reduce the metal ore powder into pure tungsten powder. This pure powder is placed in a mold and hydraulically pressed into a bar form. Because the resulting bar is very fragile, the producers must then sinter the bar. Sintering further binds the metal powder in the bar, making the bar ready for shipment to manufacturers.  

The chemical reactions and filtering relevant to refining and accomplishing the needed level of purity is a complicated and precise process, but generally results in high purity tungsten powder. Thus powder can vary in particle size and shape, depending on the intended purpose. Sometimes it remains in its powder form for use, but more often it is compressed and arranged into a solid form.

This consolidation involves a series of procedures relating to high temperatures, electrical current and an atmosphere of hydrogen. During this development, the tungsten condenses and hardens, whereupon it becomes its bar form. At this point, a tungsten bar lacks the necessary level of resilience and strength for manufacturing and must then go through further operations so that it may be rolled and drawn or flattened into its final and desired form.

The subsequent processing usually involves pulling the tungsten bar through dies, rolling it through mills and administering high temperatures and electrical currents.