Abstract: The tensile, compressive, shear tests of 044B/BA9918 aramid fiber laminates were carried out at room temperature, low temperature and high temperature. The basic mechanical properties of aramid fiber laminates in different environments and the mechanical parameters of notched specimens were obtained, such as the strength and elastic modulus of fiber and matrix, in-plane shear strength and modulus, shear strength of short beam of aramid fiber specimens. The results show that the mechanical properties of 044B/BA9918 aramid fiber laminate have strong temperature dependence. Compared with the mechanical properties in normal temperature environment, the strength and modulus values related to the matrix are enhanced in different degrees under low temperature environment, such as the strength values of 0° compression and 90° compression, while in high temperature environment, due to the degradation of matrix material performance after moisture absorption, the mechanical parameter values of the material are significantly reduced, such as in-plane shear strength.

Key words: aramid fiber composite, plasticity, constitutive relation, hot and humid environment, composites