【摘要】 采用RS-7130E型光学显微镜、D8Focus型X射线衍射仪(XRD)和带有能谱仪(EDS)的S4800型扫描电子显微镜(SEM),研究了不同熔炼温度和时间对AM60B-3Sr镁合金铸态显微组织的影响。试验结果表明:在670℃保温15min和700℃保温15min两种熔炼工艺条件下,AM60B-3Sr合金的铸态组织中都有Mg17Al12共晶相,未发现有锶化物新相形成;在730℃保温15min熔炼工艺条件下,合金的铸态组织由α-Mg枝晶和沿枝晶界分布的层片状α-Mg+Sr5Al9共晶组成;在735℃熔炼时,随保温时间的增加,共晶组织的数量增加,晶粒尺寸减小。更多还原

【Abstract】 By using of RS-7130E optical microscope, D8 Focus X-ray diffractometer, S4800 scanning electron microscope with energy spectrometer, the effects of melting process on microstructure of AM60B-3Sr magnesium alloy have been systematically investigated. Experimental results indicate that no new phase such as Al4Sr other than Mg17Al12 eutectic phase was found in AM60B-3Sr magnesium alloy in condition that holding 15 min at 670 ℃ or holding 15 min at 700 ℃, respectively. But, the Sr5Al9 new phase forms in AM60B-3Sr magnesium alloy when holding 15 min at 730 ℃, and no Al4Sr or Mg17Al12 was found. Thus, the as-cast microstructure of AM60B-3Sr magnesium alloy consists of dendritic α-Mg and α-Mg+Sr5Al9 eutectic phase. With prolonging of the holding time, the quantity of eutectic structure increases and grain size reduces when holding at 735 ℃.更多还原