precipitation in al – cu – mg alloy during creep exposure，成果详细信息-凯发网

the uniaxial tensile creep tests of al–cu–mg alloy were carried out over a wide range of temperature and applied stress. the effects of applied stress and creep aging temperature on the precipitation in al-cu-mg alloy were discussed. it is found that the precipitation process is very sensitive to the applied stress and creep aging temperature, and s phase (cumgal2) is the main precipitate under the tested creep conditions. with the increase of applied stress and creep aging temperature, s phase easily grows up and becomes sparse. meanwhile, the creep aging leads to the discontinuous distribution of precipitation phase in grain boundary, which can improve the corrosion-resistance of al-cu-mg alloy. because the lattice misfit of acicular exudation phase is far less than that of disk-shaped phase, the applied stress/strain fields will alert the competitive precipitation equilibrium between different strengthening phases. so, the large applied stress and high aging temperature easily make the preferential precipitation process as sss→gpb→s″→s′→s.