| 摘要 |
<p>1,237,049. Making articles from scrap; scrap consolidating; extruding; drawing; working at specified temperatures. HOOVER BALL & BEARING CO. 1 July, 1969 [2 July, 1968], No. 33273/69. Headings B3A, B3H, B3P and B3V. An article is formed from scrap metal by compacting the metal into a billet having a density of at least 70% of the theoretical density, heating the billet and extruding it to consolidate it to a density of substantially 100% of the theoretical density. The scrap, e.g. Ti, Zr, Mo, Nb, Ta, W, Fe in sheet, turnings &c., form is compacted at a temperature at which substantial fusion does not occur. The billet may be pierced before extrusion. The compacted billet is heated, e.g. 2000-2300‹ F. for steel and 1400-2000‹ F. for titanium, and extruded into a rod, wire, section or tube through a preheated die having a zirconia working surface. The extrusion ratio is at least 40: 1 and a lubricant of grease or a mixture of grease and glass-like material is used. A titanium or zirconium billet may be worked whilst it is enclosed in a container. The extruded rod may be cold drawn into wire.</p> |
