Effect of Zr Content on Microstructure and Mechanical Properties of Al–Mg–Si–Cu Alloy

Abstract

Effect of Zr content on microstructure and mechanical properties of Al–Mg–Si–Cu alloy were investigated by means of metallograph microscope, tensile test and transmission electron microscopy (TEM). The results show that the main precipitate is AlCuMgSi phase in Al–Mg–Si–Cu alloy after cold rolling. Zr element plays a dominant role in refinement of grains. With the increase of Zr content, numerous dislocations are found in Al–Mg–Si–Cu alloy, together with a large amount of complex phase containing Zr element precipitate within the grains. When the content of Zr is 0.7%, the tensile strength and elongation of Al–Mg–Si–Cu alloy are 490 MPa and 10%, respectively.