论文部分内容阅读
利用光学显微镜和电子探针表征了Au-Ge共晶合金的显微组织,通过DSC测试了其熔化曲线和凝固曲线,研究了添加0.2%的Sb对Au-Ge共晶合金铸态组织的影响。结果表明,添加0.2%的Sb后,Au-Ge共晶合金的初生α-Au相由针状或长杆状变为树枝状或花瓣状,其尺寸明显变小。同时,共晶组织中颗粒状的共晶Ge相的尺寸减小。初生α-Au相及共晶Ge相的细化机理分别归结为元素Sb引起的成分过冷及共晶过冷度增大。
The microstructure of Au-Ge eutectic alloy was characterized by optical microscope and electron probe. The melting curve and solidification curve were measured by DSC. The effect of adding 0.2% Sb on the as-cast microstructure of Au-Ge eutectic alloy was studied . The results show that the addition of 0.2% Sb Au-Ge eutectic alloy primary α-Au phase from acicular or long rod into dendritic or petal-shaped, its size was significantly smaller. At the same time, the size of the eutectic Ge phase in the eutectic structure decreases. The refinement mechanism of primary α-Au phase and eutectic Ge phase are attributed respectively to the overcooling of element Sb and the increase of eutectic undercooling.