【摘要】 研究了超声振动工艺参数对Zn-55Al-1.6Si合金凝固组织的影响。结果表明,Zn-55Al-1.6Si合金熔体经过超声振动处理后,凝固组织发生了显著变化。随着超声功率增大,初生α相由粗大的树枝晶变为细小圆整的蔷薇状;超声功率增至200W后,继续增大施振功率,细化效果没有明显变化。在超声功率一定的条件下,施振温度区间对凝固组织也有影响。当超声终止温度在液相线以下时,初生α相变为各向同性的蔷薇状及近球状,且超声终止温度越低,组织越细小圆整。施振功率为200W左右、施振温度区间为620～540℃时,是较为理想的超声细化处理工艺,此时粗大的枝晶状α-Al骨架变为细小球状。更多还原

【Abstract】 Effects of ultrasonic vibration on solidification structure of Zn-55Al-1.6Si alloy were investigated. The results show that solidification structure of the alloy is apparently changed after ultrasonic treatment. With increasing in ultrasonic power, primary α phase is converted from coarse dendrite into fine and round rosette one. However, when ultrasonic power exceeds 200 W, with increasing in power, refining effects can be ignored. At a given ultrasonic power, solidification structure is also related with ultrasonic temperature. When vibration-stop temperature is below liquidus temperature, primary α phase is transformed into isotropic rosette and near spherical structure. Furthermore, the lower the vibration-stop temperature is, the finer the structure is. Coarse dendritic α-Al phase is transformed into fine spherical one with ultrasonic power of approximately 200W at 540～620℃.更多还原