| 摘要 |
<p>PURPOSE:To provide an Al alloy which withstands working under a severe condition and has an excellent superplastic characteristic by specifying the compsn. consisting of Zn, Zr, Sb and Al. CONSTITUTION:A superplastic Al alloy has the compsn. contg. 4-15wt% Zn, 0.03-0.25% Zr, and 0.01-1% Sb, contg. further 0.03-3.5% Mg and/or 0.03-0.3% Cu according to need and consisting of the balance Al and unavoidable impurities. The casting ingot of the Al alloy having the prescribed compsn. is subjected to a homogenization treatment under the condition of holding the same at a temp. ranging about 400-500 deg.C for about 1-48hr and is then subjected to hot rolling at about >=50% draft in a temp. range of about 250-530 deg.C and cold rolling at about >=40% draft by which the ingot is made into a plate material having a final thickness. The temp. is preferably increased slowly to the treatment temp. at about 10-200 deg.C/min heating rate in the above-mentioned homogenization treatment, by which Zr is finely and uniformly deposited and the superplastic characteristic is assured.</p> |
