中文摘要：

采用熔体直接反应法与超声处理相结合制备原位Mg2 Si/AM60复合材料,研究超声工艺对复合材料中第二相的形貌、分布、数量以及力学性能的影响。结果表明,随着超声处理时间的延长和功率的增加,复合材料中的半连续网状 Mg17 Al12细化成颗粒状,粗大的中国汉字状 Mg2 Si 破碎成细小的中国汉字状、纤维状、颗粒状,其力学性能逐渐升高,但超声处理时间超过60s后,组织恶化,力学性能降低。超声处理时间为60s、功率为600W 制备的复合材料中的Mg17 Al12、Mg2 Si主要呈颗粒状且均匀分布,Mg17 Al12的析出受到显著的抑制,其抗拉强度和伸长率较未超声时的178.24MPa、3.56%分别提高了10.4%和48.3%,达到196.75MPa和5.28%。

英文摘要：

In-situ Mg2 Si/AM60 composites was prepared by combined melt direct reaction method with ultra-sonic treatment.Effect of ultrasonic treatment process on morphology,distribution and composition of second-ary phase and mechanical properties of in-situ Mg2 Si/AM60 composites were investigated.The results show that the morphology of Mg17 Al12 phase exhibits the change from semi-continuous net-structur into granular shape with increasing ultrasonic treatment time or ultrasonic treatment power,and coarser chinese-script Mg2 Si phase becomes finer chinese-script,fibrous and granular shape.Meanwhile,mechanical properties of in-situ Mg2 Si/AM60 composites improves gradually,but it will decrease with ultrasonic treatment time of more than 60s.Ultrasonic treatment of 600W for 60s,there exist the well-distributed granular shape Mg2 Si phase and Mg17 Al12 phase which was significant inhibited.Meanwhile,the tensile strength and elongation of in-situ Mg2 Si/AM60 composites are increased to 196.75MPa and 5.28%,increased by 10.4% and 48.3% compared with 178.24MPa and 3.56% of one without ultrasonic treatment.