采用透射电镜观察了快冷态Ti-5Al-4Sn-2Zr-1Mo-0.25Si-0.3～1.2Nd合金(Ti-55合金)稀土相的形貌,发观稀土相尺寸细小(4～34nm),呈球状,均匀弥散地分布在基体中,晶界上稀土相呈椭球状,沿晶界排列.采用图像分析仪对铸态Ti-55合金稀土相进行了分析,结果表明,4种成分合金的稀土相平均尺寸为3.25～3.50μm,平均圆度系数为0.56～0.63,呈椭球状,棒状及不规则状,分布于晶界与晶内,其均匀弥散度劣于快冷态Ti-55合金的稀土相.

Transmission eletron microscope studies of melt-quenched Ti-5Al-4Sn-2Zr-1Mo-0.25Si-0.3～1.2Nd alloy show that spherical rare earth-enriched phase particles of 4～34nm in diameter distribute fairly uniformly in the matrix,besides which,ellipsoidal particles are aligned along the grain boundary.The as-cast Ti-5Al-4Sn-2Zr-1Mo-0.25Si-0.3～1.2Nd alloy is studied by using an image analyzer,The rare earth-enriched phase particles which nonuniformly distribute in grain and grain boundary are about 3.25～3.50μm in diameter.The average value of circularity shape factor is 0.56～0.63,and the shapes of particles are mainly ellipsoids,and a few kinds of irregular morphologies like needle and block,so its uniform degree is less than the rare earth-enriched phase particles in the melt-quenched Ti-5Al-4Sn-2Zr-1Mo-0.25Si-0.3～1.2Nd alloy.