Ti/Ti-Al微叠层复合材料的微观组织与性能研究

Study on Microstructures and Mechanical Properties of Ti/Ti-Al Microlaminated Composite

采用大功率电子束物理气相沉积(EB-PVD)制备了厚度为0.12mm的大尺寸Ti/Ti-Al叠层状复合材料.利用XRD和SEM对材料的组成相和微观结构进行了分析,对致密化处理前后的试样进行了不同温度下的静拉伸试验研究.实验结果表明:材料由Ti,α2-Ti3Al和γ-TiAl相组成,具有明显的层状结构,晶粒平均尺寸为100～300nm.相对于TiAl单体材料,微叠层材料的韧性有了较大提高,经致密化处理后的试样在层间界面对裂纹的钝化作用下,具有较高的拉伸强度,并表现出良好的延迟断裂特性.

Large-sized Ti/Ti-Al microlaminated composite thin sheet with thickness of 0.12mm was prepared by high-powerful electron beam physical vapor deposition technology in laboratory.The composite and microstructure of were analyzed by XRD and SEM;samples before and after densification were evaluated with static tensile test under different temperatures.The results of experiments indicated that the prepared material with visible lamellar structure was composed of Ti and α2-Ti3Al and γ-TiAl phases and the mean grain size was about 100-300nm.The ductility of microlaminate composite has been increased compare to that of TiAl component,the sample after densification treatment has a higher tensile strength and a good characteristic of delayed fracture due to the crack bluting induced by micro-layer interfaces.