真空热压原位Al_3Ti增强Mg-Al基复合材料合成机制

Fabrication mechanism of in-situ synthesized Al_3Ti reinforced Mg-Al matrix composites by vacuum hot-pressing

采用真空热压原位合成法制备Al3Ti增强Mg-Al基复合材料。研究了烧结工艺对复合材料显微结构的影响。探讨了Al3Ti的原位合成机制,提出了Ti和Al的微观反应模型。采用XRD、SEM等方法分析了复合材料的相组成及微观结构。结果表明,Mg-Al基复合材料组织致密,原位合成增强相Al3Ti颗粒在基体中均匀分布,尺寸为0.5～2.0μm,与基体界面紧密结合,同时存在少量残余的Ti和中间相Al-Ti。

In-situ Al3Ti reinforced Mg-Al matrix composites were prepared by vacuum hot-pressing.The mechanism of in-situ synthesized Al3Ti was discussed and a model of micro structural reaction between Ti and Al was brought forward.Effects of sintering schedules on microstructures of composites were researched by methods,such as XRD and SEM.Results indicate that Mg-Al matrix composites are dense in structure,while uniformly distributed in-situ Al3Ti particulates with the size of 0.5~2.0 μm are combined closely with Mg-Al matrix.Small quantities of remnant Ti and intermediate phases Al-Ti also exist.