快速凝固Al-Fe-Ce合金显微组织及热稳定性的研究

Study on Microstructure and Thermal Stability Behavior of Rapidly Solidified Al-Fe-Ce Alloy

采用单辊旋铸法制备Al 8Fe 4Ce (质量分数 )合金薄带 ,利用透射电镜、能谱分析技术研究了该合金的急冷态和退火态组织 ,测定了合金在不同温度下退火后的显微硬度。急冷合金组织随冷速的不同而不同 ;30 0℃退火态组织无明显变化 ;40 0℃退火 2h后 ,晶界弥散相开始长大、聚集 ,但初生相变化甚微 ;450℃退火 2h后 ,初生相和晶间弥散相 (分别为亚稳相Al6 Fe和亚稳相Al2 0 Fe5 Ce相 )均进一步粗化。通过显微硬度测定可间接确定该合金的软化温度在 30 0℃以上。

Rapidly solidified Al 8Fe 4Ce alloy was prepared by melt spinning.As quenched and as annealed microstructures were studied by TEM and energy dispersive spectrum analysis.The microhardness of the alloy at different annealing temperature was measured.The results obtained indicated that as quenched microstructure varied with different cooling rates.The microstructure annealed at 300℃ was much the same as that of the as quenched.The dispersed phases at grain boundary of the microstructure annealed at 400℃ became coarsening.After annealing at 450℃ for 2 hours,the primary phase and the intercellular dispersed phases,metastable phase Al 6Fe and Al 20 Fe 5Ce respectively,coarsened further.The soften temperature was deduced at over 300℃ by measuring microhardness.