本文研究镁在钴基合金中的分布及对显微组织的作用。虽然俄歇谱仪分析未能发现在含镁合金的晶界或碳化物相界处存在镁的偏析现象,但镁的加入却使合金中原先的网状碳化物部分转变为块状,并使后者的含铬量增加。合金的形核熵理论研究表明,正是这种铬含量的提高导致了碳化物形核熵变的增加,并使形核速率显著提高。 This paper studies the distribution of magnesium in cobalt-based alloys and its effect on microstructure. Although Auger spectroscopy analysis failed to find the segregation of magnesium in the grain boundary or carbide phase boundary of the magnesium-containing alloy, the addition of magnesium led to the transformation of the original network carbides in the alloy into lumps, The latter’s chromium content increased. The study of the nucleation entropy theory of the alloy shows that it is the increase of the chromium content that leads to the increase of the entropy change of the carbide nucleation and the remarkable increase of the nucleation rate.