中文摘要：

利用扫描电镜和能谱分析研究了产生黑斑的GH3044组织，采用Thermal-Calc分析方法研究了合金凝固过程中液体成分变化，并计算了合金凝固时液体密度的变化，给出了GH3044合金平衡凝固时密度反转的范围。结果表明：合金GH3044黑斑区主要是由Cr，W的碳化物相和少量高W（Cr）的体心立方相组成，合金在凝固过程中约有0．0125g ·cm^-3·℃^-1较大的密度反转。

英文摘要：

The microstructure of GH3044 with freckles was investigated by SEM and EDAX and the variation of liquid concentration during solidification and equilibrium phase transformation was calculated by the Thermal-Calc analysis. The liquid density and the magnitude of density inversion in GH3044 during solidification were calculated. The results show that a large number of carbides and a small quantity of bcc precipitate containing rich W （or Cr） appear in freckle area. There is a high liquid density inversion of about 0.0125g ·cm^-3·℃^-1 in GH3044.