【摘要】 采用一种新型的制备工艺———电子束物理气相沉积(EB-PVD)技术,成功制备了尺寸为150mm×100mm×0.4mm的-γTiA l基合金薄板,并采用扫描电子显微镜(SEM)和X-射线衍射(XRD)等测试手段对蒸镀态及热处理态试样的物相组成和断口形貌等进行分析。结果表明,蒸镀态-γTiA l基合金薄板由γ相、α2相和τ相组成,表面质量良好,内部自然分层,显微组织结构为柱状晶。经1000℃/16h的真空退火处理后,柱状晶转变为等轴晶,τ相消失,α2相含量显著减少,同时有消除分层现象的趋势,材料的断裂方式由沿晶脆性断裂转变为沿晶脆性断裂和韧窝韧性断裂的混合断裂方式。更多还原

【Abstract】 Gamma TiAl-based alloy sheet with 150mm×100mm×0.4mm was fabricated successfully by EB-PVD process,a new technique for producing sheet.The phase composition and micrographs of fractures of the deposited and annealed samples were analyzed by SEM and XRD.The results indicated that the deposited γ-TiAl based alloy sheet was composed of γ,α₂ and τ phase,and the quality of the surface was well.There was spontaneous lamination inside the sheet and the microstructure was columnar crystal,which transformed into equiaxed crystal with τ phase disappeared,α₂ phase decreased obviously,and the lamination trended to eliminate after vacuum heat treatment at 1000℃/16h.The fracture of the material was diverted from the manner of intergranular brittle fracture to the manner of intergranular brittle fracture with dimple gliding fracture.更多还原