【摘要】 用 XRD,SEM对原位自生法制备的 Ti- 5 0 Al- x B (at% )合金的相组成和微观组织进行了研究。结果表明 :该合金主要由 Ti Al和 Ti B2 两相组成 ;Ti B2 主要以片状、板片状、细棒状和块状形式存在 ;Ti B2 微观形貌随着合金中B含量的变化而发生显著变化。当 B含量由 0 .4at%增加至 1.4at%时 ,Ti B2 的微观形貌由片状依次演变为板片状、细棒状直至块状 ,而基体形貌没有明显变化。根据 Ti B2 晶体形核与生长条件对 Ti B形貌演变过程成进行了分析更多还原

【Abstract】 The microstructure and phase constitution of Ti 50Al xB(at%)alloys produced by in situ growing method were investigated by XRD and SEM respectively The results show that these alloys are composed of TiAl and TiB 2 phase, and boron additions to TiAl alloys introduce the refractory compound TiB 2 in variety of morphologies The morphologies of TiB 2 change from convoluted flakes to needles to plates and eventually to particles as the B content increases from 0 4 at% to 1 4 at% Growth mechanism and evolution of TiB 2 morphology were analyzed according to TiB 2 crystal structure and growth condition更多还原