本研究主要的目的在於研究鐵錳鋁碳κ相 (Fe,Mn)3AlCx之晶格常數於不同溫度下之變化特性，結果發現 Fe3AlCxκ相晶格常數隨溫度的變化，於 650℃以下均保持穩定，顯示 Fe3AlCx於測量溫度範圍內，長秩有序十分穩定。而分析含錳的 (Fe, Mn)3AlCx κ相之晶格常數隨溫度的變化，發現有於 400~500℃的溫度範圍間發生熱膨脹係數異常變化的現象，而且熱處理的過程對於晶格常數變化亦有影響，此可用晶格缺陷濃度變化加以解釋，同時由晶格常數的增加現象，判斷此種晶格缺陷型態主要為 Anti-structure defect type。

The purpose of this research is to investigate the lattice constant of κ phase (Fe,Mn)3AlCx at different temperature. The results reveal that the coefficient of thermal expansion (COE) of theκphase Fe3AlCx keeps constant from room temperature to 650℃. On the other hand, the COE of theκphase with manganese content (Fe,Mn)3AlCx exhibits an unusual discontinuous feature at the temperature range of 400~500℃. Moreover the course of heat-treatment plays an important role to govern the lattice constant of the (Fe,Mn)3AlCx specimen. This can be explained by concentration variation of point defects. Meanwhile, the excess increase of the lattice constant shows that the major type of point defect is the anti-structure defect type.