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利用ＴＥＭ研究了两种定向凝固共晶合金ＮｉＡｌ－Ｃｒ和ＮｉＡｌ－（Ｃｒ，Ｍｏ）在不同状态下的显微结构特征，以能了解其复相强韧化作用。它们的显微结构分别呈棒状和层状形态。共晶两相间的界面呈半共格，存在不可动的位错网。此外，在（Ｃｒ，Ｍｏ）相上分布着细小的共格ＮｉＡｌ析出相。经形变后，ＮｉＡｌ相中的位错被界面位错网钉扎，（Ｃｒ，Ｍ０）相中未发现位错。经１３００Ｋ×５００ｈ热处理，共晶形态稳定不变，ＮｉＡｌ析出相稍显粗化。
The microstructural characteristics of NiAl-Cr and NiAl- (Cr, Mo) eutectic alloys of two kinds of oriented solidification alloys under different states were studied by TEM, in order to understand the strengthening and toughening effects of the phases. Their microstructures were rod-shaped and layered. Eutectic two-phase interface was semi-coherent, there are immobile dislocation network. In addition, a fine coherent NiAl precipitates are distributed on the (Cr, Mo) phase. After deformation, dislocations in the NiAl phase were pinned by interfacial dislocation network, and no dislocations were found in the (Cr, M0) phase. After 1300K × 500h heat treatment, the morphology of eutectic remains unchanged, and the precipitation phase of NiAl is slightly roughened.