| 摘要 |
PURPOSE:To obtain the titled ingot enabling the stable manufacture of a forged article having an acute angle by continuously casting Al or an Al alloy so as to provide a shape having an acute angle in its cross-section while specifying the grain size of the structure and the space between secondary dendrite arms. CONSTITUTION:Al or an Al alloy is continuously cast by a hot top continuous casting method using a gas pressure impressing system or other method so as to provide a deformed cross-section having at least one acute angle as shown by the figures, and the cooling rate is properly selected as to form a structure in which >=85% of the grains have <=180mum grain size and >=90% of the spaces each between secondary dendrite arms are <=25mum. The resulting Al or Al alloy ingot can be used as cast to manufacture stably an Al or Al alloy article having an acute angle by plastic working, cold forging or other forming.
|
