| 摘要 |
PURPOSE:To obtain an Al-alloy member excellent in mechanical properties and dimensional accuracy, by forming an Al alloy having specified compositional ranges into a near-final shape by increasing a forging ratio in the required part and then by subjecting the resulting forged stock to finish forming by partially changing the forging ratio. CONSTITUTION:The Al alloy has a composition principally consisting of, by weight, 4.0-7.5% Si, 0.2-1.2% Mg, <=0.5% Cu, and the balance essentially Al. By increasing the forging ratio in the part requiring strength and resistance to pressure and by reducing the forging ratio in the part other than the above, this Al alloy is forged into a stock of near-final shape, which is maintained at about 300-500 deg.C and subjected to finish forging by an impression method. In this way, the Al-alloy member in which internal defects are removed and which has complicated shape can be obtained.
|
