Influence of Some Processing Variables Upon the Elevated and Room Temperature Strength of Ultrafine Beryllium Wires

摘要

An ultrafine beryllium wire was produced with a strength of approximately 150 ksi at room temperature and possessing excellent elevated temperature ductility. The application of a nickel coating to the wire allays the effects of transverse crack formation in the beryllium core until complete separation of the metals at the beryllium-nickel interface occurs at 1100F. As a result of this protection, the elevated temperature tensile strength of the nickel clad wire is substantially greater than bare beryllium wire at all temperatures and nearly twice that of bare wires in the temperature range 600-1100F. The effect of a Ti02 coating on some of the wires processed from ingot material, however, must be considered inconclusive because of the damaging influence of poor surface quality of the beryllium core. The chemical-milling procedure not only improves the surface quality vastly, but tensile strength at room temperature can be increased by as much as 30 ksi.