The first known successful cold extrusion of titanium was accomplished at Battelle on a project for Wright Air Development Center. Working with commercially pure grades of titanium having 45,000 and 70,000-psi yield strengths, and employing a Battelle-developed fluoride-phosphate coating for titanium, billets 1½ in. diam were forward extruded to bars 1.16, 1.06, and 0.95 in. diam. These correspond to reductions of 40, 50, and 60 per cent. The fluoride-phosphate coating, in combination with a conventional oil-graphite-molybdenum disulphide lubricant, prevented seizing and galling and produced a smooth surface finish. The extruded bars exhibited as high as a 60 per cent increase in strength, yet adequate ductility (10 per cent in 1 in. minimum) was maintained.

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