热压温度对TC4/Ta层状复合材料界面元素扩散行为及微观结构的影响

Effect of hot-pressing temperature on element diffusion behavior and microstructure of TC4/Ta layered composites

在不同温度下通过高温热压复合制备了TC4/Ta/TC4层状金属复合材料(LMCs),并讨论了界面元素扩散行为、微观结构随热压温度的变化关系。结果表明,在热压和保温过程中两组元元素在界面处发生了明显的扩散行为,两组元实现了良好的冶金结合。高温热压促进了Al、V、Ti、Ta各元素在界面处的扩散,其扩散程度显著影响了界面附近的显微组织。每种元素的扩散深度与原子半径紧密相关,随着原子半径减小,扩散行为发生的更为强烈。元素扩散行为导致界面附近钛基体的相变温度降低,在低于TC4相变温度的950℃出现了网篮组织,随着与界面距离的变化呈现不同的微观组织形貌。

TC4/Ta/TC4 layered metal composites(LMCs)were prepared by hot-pressing at different temperatures,and the diffusion behavior of interfacial elements and the microstructure at different temperatures were discussed.The results show that obvious diffusion behavior occurs at the interface during the process of hot-pressing and holding,and the two groups achieve good metallurgical bonding.High temperature hot-pressing promotes the diffusion of Al,V,Ti and Ta,and the degree of diffusion significantly affects the microstructure near the interface.The diffusion depth of each element is closely related to the atomic radius.As the atomic radius decreases,the diffusion behavior occurs more intensely.The element diffusion behavior leads to the decrease in the phase transition temperature of the titanium matrix near the interface,and the basketweave structure appears at 950℃below the phase transition temperature of TC4.The microstructure changes with the change of the interface distance.