effect of creep-凯发网

the creep-aging behaviors of 7075 aluminum alloy are studied by uniaxial tensile creep experiments under elevated temperatures. the effects of creep-aging temperature and applied stress on the precipitates of 7075-t651 aluminum alloy are investigated using scanning electron microscope (sem) and transmission electron microscope (tem). results show that: (1) coarse insoluble precipitates ( and ) and intermediate precipitates ( and ) are found in the aluminum matrix, and the effects of creep-aging treatment on these precipitates are not obvious; (2) the main aging precipitates are and phases, and the aging precipitates grow up with the increase of creep-aging temperature and applied stress; (3) with the increase of creep-aging temperature and applied stress, the precipitates are discontinuously distributed on the grain boundary, and the width of precipitate free zone increases with the increase of creep-aging temperature and applied stress; (4) compared with the microstructure in the traditional stress-free aged sample, the creep-aging process can refine the precipitates and narrow the width of the precipitate free zone.