Influence of Al particle layer on damping behavior of Alp/7075Al composites fabricated by hot rolling

Abstract The Al particle reinforced 7075 Al matrix composites with the layered structure are prepared by hot rolling to improve the damping property of the alloy. Numerous interparticle interfaces are observed in the Al particle layer (reinforcement), and the traces of no interfacial reaction or elemental diffusion are found between the matrix and reinforcement layer. The tensile strength of the composite is 29% higher than that of the matrix. The internal friction values of the Alp/7075Al lamellar composite and the 7075 Al matrix are found to increase with the increase in temperature and strain, respectively. At 570 K, the internal friction values of the composites are found to be as high as 0.105, which is 337% higher than that of the matrix, and an internal friction peak (P2) appears in the composites due to the recrystallization of Al particles at high temperature. The comprehensive damping index of the composite is found to be about 2.9-fold of the 7075 Al matrix. The damping mechanism of the composite is mainly attributed to dislocation damping, grain boundary damping, and interface damping.