利用与时间有关的瞬态形核理论计算了不同Nd含量的Al Fe V Si Nd合金中α Al相的形核率、形核孕育期与过冷度的关系 ,并计算了α Al形成非晶的临界冷却速率。结果表明 ,随Nd含量增加 ,合金的液相线温度提高 ,α Al形核孕育期延长 ,形核...利用与时间有关的瞬态形核理论计算了不同Nd含量的Al Fe V Si Nd合金中α Al相的形核率、形核孕育期与过冷度的关系 ,并计算了α Al形成非晶的临界冷却速率。结果表明 ,随Nd含量增加 ,合金的液相线温度提高 ,α Al形核孕育期延长 ,形核过冷度增加 ,形核率降低 ,临界冷却速率降低 ,从而增大其非晶的形成倾向。展开更多
采用透射电子显微镜和正电子湮灭技术研究了低周疲劳过程中快凝Al Fe V Si Nd合金微结构的变化 ,发现 :经高载荷循环后晶内固溶元素析出产生偏聚体 ,且随循环次数的增加 ,偏聚体长大 ;当循环次数达到 15 0 0次后 ,随循环次数的继续增加 ...采用透射电子显微镜和正电子湮灭技术研究了低周疲劳过程中快凝Al Fe V Si Nd合金微结构的变化 ,发现 :经高载荷循环后晶内固溶元素析出产生偏聚体 ,且随循环次数的增加 ,偏聚体长大 ;当循环次数达到 15 0 0次后 ,随循环次数的继续增加 ,大于临界尺寸的偏聚体长大而小于临界尺寸的偏聚体重新溶解·展开更多
Rapidly solidified Al 8.4Fe 1.3V 1.7Si heat resistant alloy was made by using multi layer spray deposition technique. Its thermal stability of mechanical properties was investigated by the means of tensile and hardnes...Rapidly solidified Al 8.4Fe 1.3V 1.7Si heat resistant alloy was made by using multi layer spray deposition technique. Its thermal stability of mechanical properties was investigated by the means of tensile and hardness tests, thermal stability of microstructure by transmission electron microscopy (TEM), X ray diffraction (XRD). The results show that after heat exposure (HE) at 753?K for 500?h the tensile strength and hardness of Al Fe V Si alloy at 623?K maintains the same values as those at room temperature. HE dose not obviously affect the thermal stabilities of Al 12 (Fe,V) 3Si phase but the lattice constant of Al 12 (Fe,V) 3Si phase decrease.展开更多
文摘采用透射电子显微镜和正电子湮灭技术研究了低周疲劳过程中快凝Al Fe V Si Nd合金微结构的变化 ,发现 :经高载荷循环后晶内固溶元素析出产生偏聚体 ,且随循环次数的增加 ,偏聚体长大 ;当循环次数达到 15 0 0次后 ,随循环次数的继续增加 ,大于临界尺寸的偏聚体长大而小于临界尺寸的偏聚体重新溶解·
文摘Rapidly solidified Al 8.4Fe 1.3V 1.7Si heat resistant alloy was made by using multi layer spray deposition technique. Its thermal stability of mechanical properties was investigated by the means of tensile and hardness tests, thermal stability of microstructure by transmission electron microscopy (TEM), X ray diffraction (XRD). The results show that after heat exposure (HE) at 753?K for 500?h the tensile strength and hardness of Al Fe V Si alloy at 623?K maintains the same values as those at room temperature. HE dose not obviously affect the thermal stabilities of Al 12 (Fe,V) 3Si phase but the lattice constant of Al 12 (Fe,V) 3Si phase decrease.