| 摘要 |
1,085,034. Altering physical structure. COMMISSARIAT A L'ENERGIE ATOMIQUE. Oct. 15, 1964 [Oct. 25, 1963], No. 42142/64. Heading B3V. In the manufacture of beryllium products, particularly casings for fuel rods in nuclear reactors, an ingot of cast beryllium is subjected to a hot working operation, then to forging and finally to at least one extrusion operation. An ingot may be encased in soft steel 2 mm. thick and compressed at 800‹ C. before the hot working operation which may be an extrusion at 900‹ C. A billet sliced from the resulting bar and with a steel casing 10 mm. thick is forged in a press after heating to 1000‹ C. to reduce its height by a quarter. The steel casing is removed and the billet machined, drilled and coated with a thin silver layer. It is then impact extruded at 900‹ C. Tubes thus obtained are said to have increased ductility and to have the base planes of the elemental crystallites disposed chiefly in parallel relationship to the extruding direction, the maximum angular distribution of the planes being in a tangential direction. |
