| 摘要 |
PURPOSE:To improve machinability and to increase strength, by performing finishing comprising compressing machining of a raw strip after the final annealing in the direction of the width and rolling in the longitudinal direction, and reducing anisotropy in the direction of the width and in the longitudinal direction. CONSTITUTION:Finishing comprising compressing machining of a raw strip in the width direction after the final annealing and rolling in the longitudinal direction is performed. Therefore, anisotropy becomes less, the machinabilities and the strengths in the longitudinal direction and the width direction become approximately equal. Package machining such as QFD (quad flat package) and PLCC (plastic leaded chip carrier) can be performed. Namely, a machining rate, which is larger than that in the machining in one direction, can be applied by combining the compressing machining for providing the width and the ordinary rolling. Thus the level of the strength can be increased.
|
