| 摘要 |
PURPOSE:To obtain the Al base alloy plate for magnetic discs which is easy to polish and is highly smooth by continuously casting Al base alloy molten metal contg. specific ratios of Mg, Mn, Fe, Zn, Cr, etc. to a specific thickness then rolling the same. CONSTITUTION:An Al base alloy essentially contg. 2-6% Mg, <=1% Mn, <=0.3% Fe, <=0.25% Zn, <=0.35% Cr as alloy elements, and further selectively contg. <=0.08% Ti, and/or <=0.01% B is prepd. The used Al is of about >=99% purity. This molten metal is continuously cast to 4-15mm. thickness, and is further hot, warm or cold rolled, whereby an Al base alloy plate is obtd. This alloy plate is obtained in the state that extremely fine crystals are uniformly dispersed. |
