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使用俄歇电子谱仪（ＡＥＳ）、透射电镜结合能谱仪（ＥＤＡＸ）及扫描电镜等分析仪器，研究了用双真空（真空感应熔炼＋真空自耗重熔）工艺生产的钴基高温合金ＧＨ１８８中稀土镧化物的析出形貌与类型以及添加的微量元素Ｍｇ晶界偏聚的特性。研究结果表明，采用双真空工艺重熔后，合金中的镧化物呈不均匀分布，导致以它为形核点析出的部分碳化物也分布不均，使其弥散强化效果变差。该合金中的镧化物主要有Ｌａ２Ｏ３，Ｌａ２Ｏ２Ｓ，ＬａＯＳ２，Ｌａ２Ｓ３等类型。另外，微量元素Ｍｇ在合金中的晶界偏聚较为明显，这将降低合金的热加工性。因此，ＧＨ１８８合金中应限制元素Ｍｇ的含量或不加Ｍｇ
Using Auger electron spectroscopy (AES), transmission electron microscopy (EDAX) and energy dispersive spectroscopy (EDAX), scanning electron microscopy (SEM) and other analytical instruments, the cobalt base superalloy GH188 produced by double vacuum (vacuum induction melting and vacuum consumable remelting) Lanthanide rare earth lanthanide precipitation morphologies and types and added trace element Mg grain boundary segregation characteristics. The results show that, after double vacuum process remelting, the lanthanides in the alloy are unevenly distributed, leading to the uneven distribution of some carbides precipitated by it as nucleation sites, which makes the dispersion strengthening effect worse. The lanthanides in the alloy are mainly La2O3, La2O2S, LaOS2, La2S3 and other types. In addition, the trace element Mg in the grain boundary segregation is more obvious, which will reduce the hot workability of the alloy. Therefore, GH188 alloy should limit the content of elemental Mg or without Mg