Improvement of strength of B/Al composite by thermal-mechanical cycling

来源期刊：中国有色金属学报(英文版)2004年第5期

论文作者：覃耀春 何世禹 杨德庄

文章页码：907 - 911

Key words：B/Al composite; thermal-mechanical cycling; microstructure; mechanical properties

Abstract: The mechanical properties of B/Al composite were measured at room temperature in the as-fabricated condition and after thermal-mechanical cycling(TMC). The effects of TMC on microstructure and tensile fracture behavior of B/Al composite were studied using transmission electron microscope(TEM) and scanning electron microscope(SEM). The fibers/matrix interfaces are degraded during TMC, the extent of which is enhanced with increasing the cycles, causing a measurable decrease of stage modulus of the B/Al composite. The TMC induces the dislocation generation in the aluminum matrix and the dislocation density increases with the cycles. The synergistic effect of the matrix strengthening and the interfacial degradation during TMC is found to play an important role in controlling the changes of tensile strengths and fracture behavior of the composite. The ultimate tensile strength of the composite increases with the cycles increasing. The interfaces in the B/Al composite change from the strongly-bonded states toward the appropriately-bonded ones with increasing the cycles. TMC will provide an approach of improving the strength of B/Al composites.