功率超声对Al-Si合金组织和性能的影响

Effect of high intensity ultrasounic on structures and properties of Al Si alloys

研制成功率超声铸造设备和附属装置， 研究了全过程超声处理和结晶前超声处理对ＡｌＳｉ 共晶和过共晶合金铸造组织和性能的影响。结果表明： 适宜的超声参数对初晶Ｓｉ 和共晶Ｓｉ 组织具有双重细化作用， 使Ｓｉ 破碎变成颗粒状， 合金的机械强度和塑性明显提高。认为超声细化合金组织存在阈值声压， 对功率超声细化合金组织的机理进行了理论上的分析和探讨。

The casting device of ultrasonic vibration was designed. The effect of high intensity ultrasounic on the structures and properties of the eutectic and hypereutectic Al Si alloys was studied. It is shown that appropriate ultrasounic parameters can fine both the primary Si and the eutectic Si, Si phase is broken off into globular thus raising the strength and plasticity of the alloys remarkably. The mechanisms of ultrasonic action were investigated experimentally and approached theoretically, on the basis of which it is concluded that there exists an ultrasonic intensity threshold in fining the alloy structures.