Temperature-dependent buckling and mode jumping analysis of axially compressed composite profiles

Abstract This paper examines the thermomechanical behavior of composite materials under axial compression across a wide temperature range, focusing on buckling mode transitions. Experimental tests were conducted using a servo-hydraulic MTS system at temperatures from − 20°C to 80°C. Load-displacement and load-deflection data were collected via a 3D DIC system, ensuring accurate characterization of the buckling response. The results reveal a significant impact of temperature on the critical load and buckling mode evolution. Mode transitions at higher temperatures as well as during the loading were marked by changes in the number of half-waves in the buckling pattern. Lower temperatures increased stiffness and critical loads, while higher temperatures induced ductile behavior, reducing the critical load and allowing larger displacements before failure. These findings highlight the crucial role of thermal effects in composite stability and reliability, aiding the design of aerospace and high-performance structures.