单项选择题
A.AlO B.AlO2 C.Al2O3 D.Al2O5
A.高纯铝 B.含铜的铝合金 C.铝-镁系 D.铝-锰系
A.Cr18%、Ni8%、Mn2% B.Cr12%、Ni3%、Mn10% C.Cr18%、Ni3%、Mn2% D.Cr12%、Ni8%、Mn4%