【摘要】 利用光学显微镜、扫描电镜和X射线衍射仪等研究了GH4169合金返回料中枝晶和夹杂物的形貌、尺寸及分布特征。通过与合金新料微观组织进行对比，分析了凝固过程中返回料中枝晶的生长过程与夹杂物的形成原因。结果表明：GH4169返回料中的合金元素种类与新料基本相同，但N、O含量明显增加。返回料的凝固组织为柱状晶，生长方向为由边缘向心部生长。一、二次枝晶臂间距变化规律一致，越靠近试样中心，枝晶间距越大，枝晶间存在NbC、TiN的夹杂和Laves+NbC的两相夹杂。返回料试样从中心到边缘显微硬度呈逐渐增加的趋势，晶间存在的夹杂物对合金的硬度影响不明显。更多还原

【Abstract】 Morphology, size and distribution characteristics of dendrites and inclusions in GH4169 revert alloy were studied using optical microscope, scanning electron microscopy and X-ray diffraction. By comparing the microstructure of the revert alloy and the virgin alloy, the growth process of dendrites and the formation reasons of inclusions in the revert alloy during solidification were analyzed. The results show that the alloy elements in the GH4169 revert alloy are basically the same as those in the virgin alloy, but the N and O content increases significantly. The solidification structure of the revert alloy is columnar crystals, and the growth direction is from the edge to the center. The variation law of primary and secondary dendrite arm spacing is consistent. The closer it is to the center of the sample, the larger the dendrite spacing. There are inclusions of NbC and TiN and two-phase inclusions of Laves+NbC between the dendrites. The microhardness of the revert alloy shows a gradually increasing trend from the center to the edge, and the presence of intergranular inclusions has little effect on the hardness of the alloy.更多还原