The mechanical properties and microstructure of three different Cu contents of Al-xCu-Mg-Ag-Mn-TiZr-Sc（x=5.23

5.56

5.82）alloys were investigated.The results reveal that the tensile strength of the three kinds of alloys at room temperature is varied slightly

however the creep properties at high temperature is changed greatly.The creep properties of the under-aged alloy with 5.82% Cu content present desirable effects.At high temperature（200 MPa/240℃）

the creep fracture time reaches 64.43 hof the alloy with 5.82% Cu content

which is about 3 times of the others.And at high tension（250 MPa/200℃）

the steady creep rates of alloy with 5.82% Cu content is 6.47×10

-7

s

-1

which is about 2/5 of the others.The main strengthening phases in the three kind of test alloys areΩphases

however theΩphases′densities are varied widely.In addition

there exist also a large number of deformed W-AlCuScZr phases.