Influence of composition and heat-treatment on damping capacity of Cu-Al alloys

The compositions, structures and properties of four kinds of Cu-Al alloys with different constituents were researched by means of optical microscopy, scanning electron microscopy, X-ray diffractometry and damping detection. The structures and properties of Cu-llAl-5Mn-RE experienced different heat-treatment processes were also studied. The results indicate that the damping capacity and microstructure of the alloys are improved by adding Mn and RE elements. Cu-llAl-5Mn-RE obtains the best comprehensive physical performance because of the cooperation of Mn and RE elements. Aging at 200 ℃, the damping capacity gets to the maximum. At 400 ℃, its mechanical property decreases while its damping capacity still remains, indicating its resistance to martensite decomposition and aging at moderate temperature.