Processing Sequence

Manufacturing a consolidated, fully dense beryllium product involves ingot melting and casting, powder manufacture, and consolidation. The consolidated product usually is a right circular cylinder that is made by vacuum hot pressing. This vacuum hot pressed billet can be readily machined into parts for satellites, aircraft, optical systems, or guidance instruments. Beryllium is particularly well suited to these applications because of its superior strength, modulus, and density. The ductility afforded by P/M processing also facilitates forging, rolling, extruding, and other hot-working processes.

Raw Material. Extraction begins with the mining of bertrandite ore, Be4Si2O7(OH)2, and/or beryl ore, 3BeO-Al2O3-6SiO2, from domestic and international sources. This is converted to crude beryllium hydroxide product, purified, converted to anhydrous beryllium fluoride, and reduced with magnesium to produce "pebble" or primary beryllium. Residual reduction slag containing these beryllium pebbles is purified by vacuum melting. Vacuum melting uses a magnesium oxide crucible and a graphite mold to produce an ingot weighing 180 to 200 kg (400 to 450 lb). The ingot is "skinned" (machined) to remove the high-carbon material adjacent to the mold wall. Next, a multihead cutting tool is used to reduce the ingot to chips. Standard P/M techniques are used for powder production at this stage.

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