Abstract:This paper presents an orthogonal experimental design on the creep aging test for 7055T7751 aluminum alloy by uniaxial stretch. An empirical formula on calculating the yield strength from the prestress, aging temperature and aging duration after creep aging is obtained by analyzing the experimental results using the orthogonal polynomial regression method. In addition, the effects of the three process parameters on the yield strength of 7055T7751 aluminum alloy after creep aging are investigated