Abstract:

We addressed the impact of magnesium element on the microstructure and mechanical properties of extruded high aluminum zinc alloy. Results show that tensile strength of alloy increases from 366 MPa to 467 MPa for 0.015% Mg addition, as compared with none Mg alloy. Its brinell hardness increases from HB91 to HB114 and extension rate decreases from 43.6% to 27%.For solution treatment of 320 ℃×2 h water quenching,its tensile strength increases from 389 MPa to 488 MPa, its brinell hardness increases from HB107 to HB139 and extension rate decreases from 41% to 28.3%. Mg element can affect transformation of supersaturated β phase and morphology of decomposition product, and hinder alloy eutectoid decomposition and dissolution precipitation at room temperature.

Key words: deformation zinc alloy, extruding, mechanical property, high aluminum zinc alloy, microstructure