| Al-10wt% Ti alloy was rapidly solidified by N₂gas atomization process, and the resulting alloy powders were consolidated by hot extrusion with an extrusion ratio of 17 : 1. The characteristics of the powders and the microstructures of the powders and extrudates have been examined by using a combination of particle size analyser, X-ray diffractometer, and optical, scanning electron and transmission electron microscopes. At-10wt% Ti powders show a spherical shape with mean particle size of 50㎛, and a microstructure of equiaxed α-Al grain of 2-3㎛ with Al₃Ti particles. Powders smaller than 44㎛ consist of α-Al, Ll₂metastable Al₃Ti and DO_(22) equilibrium Al₃Ti. With increasing th powder size, metastable Al₃Ti particles disappears and equilibrium Al₃Ti particles with a petal like shape become dominant. The metastable and equilibrium Al³,Ti particles show following orientation relationships with the surrounding α-Al matrix :［100]_(Al)//［001］DO_(22)-Al₃Ti and［010］Ll₂-Al₃Ti;［100］_(A1)//［100］Ll₂-Al₃Ti and［010］_(Al)//［010］Ll₂-Al₃Ti Extrudates show a uniform show a uniform distribution of equilibrium Al₃Ti particles in α-Al matrix with grain size of 2㎛ |
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