快速凝固Al-Ti-Fe系合金的组织演化

Evolution of Rapidly Solidified Al-Ti-Fe System Alloys

采用单辊旋铸技术制备Al-2.5Ti-2.5Fe,Al-2.5Ti-2.5Fe-2.5V和Al-2.5Ti-2.5Fe-2.5Cr(at%,下同)合金薄带,利用X射线衍射(XRD)和透射电镜(TEM)分析了这些合金的急冷态和退火态组织。结果表明:快速凝固Al-2.5Ti-2.5Fe合金急冷态组织中存在Al3Ti和Al5Ti2两种初生相,快凝合金经400℃退火10h后,组织中出现了Al13Fe4相,在450℃退火,组织中析出了弥散Al3Ti相;快速凝固Al-2.5Ti-2.5Fe-2.5V合金急冷态组织中存在Al11V相和Al80V20相,400℃退火10h后,初生Al11V相转变为Al80V20相,且固溶在α-Al基体中的Ti,Fe以Al23Ti9相和Al13Fe4相的形式析出;快速凝固Al-2.5Ti-2.5Fe-2.5Cr合金急冷态组织中存在Al3Ti和Al13Cr2两种初生相,快凝合金经300℃退火10h后,组织中析出了Al13Cr2和Al3Ti两种弥散相,400℃退火10h时后组织中出现了Al13Fe4相。

Rapidly solidified Al-2. 5Ti-2. 5Fe, Al-2. 5Ti-2. 5Fe-2. 5V and Al-2. 5Ti-2. 5Fe-2. 5Cr(at%) alloys were produced by melt spinning. The microstructures of as-quenched and as-annealed alloys were studied by X-ray diffraction (XRD), transmission electron microscopy (TEM) and energy dispersive spectrum(EDS) analysis. The results obtained indicated that the as-quenched Al-2. 5Ti-2. 5Fe alloy consists of primary phases Al3Ti and Al5Ti2. The stable phase Al13Fe4 was precipitated in the super saturated solid solution(4s) after annealing at 400degreesC for 10 hours and there was the dispersive phase Al3Ti in the structure of alloy annealing at 450degreesC. The microstructure of as-quenched Al-2. 5Ti-2. 5Fe-2.5V alloy included two kinds of primary phases: Al-11 (V, Ti) and Al-80 (V, Ti)(20). The primary phases Al-11 (V, Ti) was completely converted into Al-80(V, Ti) (20), and Al23Ti9 and Al13Fe4 phase were precipitated in the 4s structure after annealing at 400degreesC for 10 hours. The microstructure of as-quenched alloy included two kinds of dispersed phases: Al3Ti and Al13Cr2 which were precipitated in the 4s structure after annealing at 300degreesC for 10 hours. After annealing at 400degreesC for 10 hours, the stable phase Al13Fe4 was appeared in the structure.