| 摘要 |
1,149,025. Altering molecular structure. STANDARD PRESSED STEEL CO. 27 April, 1966 [30 April, 1965], No. 18453/66. Heading B3V. [Also in Division C7] An alloy comprising 0-0À5% each of C, B, O, N and Be with the total amount thereof being no more than 0À1%. 0-2% each of Mn, Al, Ti and Zr with the total amount thereof being no more than 4%, 0-0À02% each of H, S and P, the balance, apart from impurities, being Co in an amount of at least 25%, with a ratio per cent Ni + per cent Co/per cent Cr of at least 2À6, is formed into an article and is work strengthened by reducing its cross-sectional area by 5-60% while it is below the upper temperature of its transformation zone (defined as the temperature zone above which a face-centred-cubic crystal form of the alloy is stable under the application of stress). The alloy may be made by melting processes or by atomizing a melt, optionally grinding the particles, and then compacting and sintering them. The work strengthening may be by forging, rolling, swaging, extruding, coining, drawing, tube reducing, explosive treatment, impact loading or pressing. The transformation zone varies depending on the alloy but may typically be 800-1700‹ F. The alloy may be worked between the upper temperature of the transformation zone and the melting point thereof prior to treatment according to the invention. Various homogenizing and annealing treatments are also described. The articles made by the process may be hightemperature fasteners, dies and other tools. |
