Fabrication of Tungsten and Tungsten-25%-Rhenium Tubing

Techniques were developed for the fabrication of seamless tungsten and tungsten-25%rhenium tubing. Appropriate procedures were established for primary extrusion, re-extrusion, and warm drawing. The extrusion uses the filled-billet technique, with molybdenum serving as the expendable filler which is subsequently removed chemically. Tubing diameters studied were from ≈½ in. to < 0.1 in., wall thicknesses being ≈0.1 times the diameter. A lot of 64 ft of W-25% Re tubing, 0.250-in. o.d. × 0.020-in. wall, was produced by primary extrusion and a series of moving-mandrel draws.