Effect of loading rate and height-diameter ratio on compression characteristics of aviation alloys

Loading rate and height-diameter ratio are important factors affecting mechanical properties of materials. In this paper, the effects of the two factors on the stress-strain curves and section deformation characteristics of titanium alloy and aluminum alloy were compared by uniaxial compression tests. The gray correlation coefficient between compressive strength and loading rate, height-diameter ratio, and high compression ratio of the two alloys was calculated by using the gray correlation theory, and multiple regression models of compressive strength of the two alloys were established based on the least squares method. The results show that (i) the gray correlation coefficient of the two alloys is greater than 0.6, indicating that loading rate and height-diameter ratio have obvious effects on the compressive strengths of aluminum alloy; (ii) of loading rate and height- diameter ratio, loading rate has more significant effect on compressive strength; and (iii) the correlation coefficient of the regression model of titanium alloy compressive strength is 0.9, which is higher than that of the corresponding model of aluminum alloy (0.65), indicating that the reliability of the regression model of titanium alloy is higher than that of aluminum alloy, and the established model can better predict the uniaxial compressive strength of titanium alloy.