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用ＥＥＴ 计算了Ｌ１２ 结构Ａｌ６７ Ｍｎ８Ｔｉ２５ 合金的键结构， 键能和主要解理面的解理能。结果表明几种低指数晶面的解理能以｛１１０｝ 晶面为最低， 其值为３ ．１２Ｊ·ｍ － ２ ； 其次为｛１００｝ 和｛１１１｝ 型晶面， 解理能分别为４ ．１７ 和４ ．８７Ｊ·ｍ － ２ 。用电子背散射衍射技术对合金室温弯曲断口解理刻面的晶体学位向进行了测定， 在所测刻面中，｛１１０｝ 刻面约占５４ ％ ，｛１００｝ 和｛１１１｝ 约占３１ ％ 和８ ％ ， 其结果与ＥＥＴ 计算结果相一致。可以认为， 解理能低是Ａｌ６７ Ｍｎ８Ｔｉ２５ 合金室温脆性解理的主要原因之一。
The bond structure, bond energies and cleavage energies of the L12 Al67 Mn8Ti25 alloy were calculated by EET. The results show that the cleavage energy of several low index planes is the lowest with the {110} plane and the value is 3. 12J · m - 2, followed by {100} and {111} crystal planes, respectively. 17 and 4. 87J · m - 2. The crystallographic orientation of cleavage facet at room temperature was measured by electron backscatter diffraction technique. The {110} facets accounted for about 54%, {100} and {111} about 31 % And 8%, the results of which are consistent with the EET calculations. It can be considered that the low cleavage energy is one of the main reasons for brittleness cleavage at room temperature of Al67 Mn8Ti25 alloy.