快速凝固二硼化钛增强铝硅复合材料粉末的组织特征及凝固行为  

Microstructures and Solidification Behavior of Rapidly Solidified Ti B2 Reinforced Al-Si Composite Powders

作　　者：陈梦星 陈哲[1] 张丰果 王浩伟[1] 

机构地区：[1]上海交通大学材料科学与工程学院金属基复合材料国家重点实验室

出　　处：《热加工工艺》2018年第2期133-136,共4页Hot Working Technology

摘　　要：利用真空气雾化技术制备二硼化钛增强Al-Si复合材料粉末。采用FIB、XRD、扫描电镜和透射电镜技术,对粉体的相组成和显微形貌进行了表征,探究了粉体晶粒尺寸影响因素。结果表明：快速凝固得到的复合材料粉体内部呈细小的等轴晶结构,共晶硅以板条状形式分布于α-Al晶界处,大部分二硼化钛颗粒在晶体内部弥散分布。平均晶粒尺寸与粉体尺寸呈正相关关系。快速凝固实验条件以及Ti B2颗粒的引入都可以促进晶粒细化,但前者的影响更为突出。The Ti B2 reinforced Al-Si composite powders were synthesized by vacuum gas atomization method. The phase composition and microstructures of the composite powders were characterized by means of FIB, XRD, SEM and TEM techniques. The influence factors on the grain size of the powder were studied. The results show that the composite powders prepared by rapid solidification exhibit fine grain equiaxed structures. Eutectic silicon distributes along the grain boundaries ofα-Al in the form of lath and most of the Ti B2 particles are dispersed inside the grains. The average grain size is positively correlated with powder size. The fast cooling condition and the Ti B2 particles can both promote the grain refinement, but the former has a more significant influence.

关 键 词：快速凝固 气雾化 复合材料 晶粒尺寸 

分 类 号：TG244.3[金属学及工艺—铸造] TB333[一般工业技术—材料科学与工程]