Age softening phenomenon and microscopic mechanism of Li−B alloy

The age softening phenomenon of the Li−B alloy was investigated by a series of tensile tests under various aging conditions. The results show that the tensile strength of the rolled Li−B alloy decreases with increasing aging time. Higher aging temperature accelerates the softening process, and leads to an early end of aging. A model was proposed to analyze the mechanism of the age softening. The vacancy annihilation is the control factor of age softening. The strength−temperature relationship was estimated by the newly proposed model and a standard heat treatment, annealing at 150 °C for 1 h, was designed to eliminate the age softening of rolled Li−B alloy.