摘要
用XDTM法制备了TiB2/Ti Al复合材料并利用XRD、SEM和TEM对复合材料的相组成和微观组织进行了研究。结果表明:复合材料中棒状TiB2的{1010}面存在与[0001]晶向垂直的薄片状凸耳,其厚度一般小于0.2μm,伸出表面高度可达4μm,并且这些凸耳的晶面取向与棒状TiB2本身是相同的;棒状TiB2一般以垂直交叉的十字或数个十字构成的辐射状形式分布于α2/γ层片基体中;在较快的凝固过程中,棒状TiB2固液界面前沿产生的富Al、Ti边界层和随着棒状TiB2晶体的长大,导致固液界面上B原子过饱和度不均匀性增加,共同作用使固液界面失稳,从而形成了棒状TiB2的形貌特征。
The microstructure and phase constituent of TiB_2/Ti-Al composites prepared by XD^(TM) were investigated by XRD,SEM and TEM.It was found that there exists a flake convex facets with (0.2 μm) a lower than thickness whose length reached up to 4 μm on the surface in {1010} facets perpendicular to 〔0001〕orientation of TiB_2 needles,and the orientation of the convex facets is parallel to that of TiB_2 needles.TiB_2 needles,which exists in cruciated or radicalized form,were dispersed at α_2/γ lamellar matrix.The Al-riched and Ti-riched layers and heterogeneity in supersaturation solution at solid-liquid interface resulted from non-equilibrium solidification may keep solid-liquid interface stable to result in the formation of the structure characteristic of the TiB_2 needles.
出处
《特种铸造及有色合金》
CAS
CSCD
北大核心
2005年第6期321-322,共2页
Special Casting & Nonferrous Alloys
基金
金属精密热加工国防科技重点实验室开放基金资助项目(99JS61.5.1.ZS6102)
