由於錳鋁合金鋼在市場上具有其發展潛力，以及718超合金在高溫結構材料上的重要地位，因此本篇論文選擇此兩種合金材料進行研究。
而藉由對材料施以不同條件的熱處理，以及透過使用各項儀器進行金相組織觀察與晶體結構分析，針對材料的微觀結構變化進行一系列的探討與研究。
其中，錳鋁合金鋼在穿透式電子顯微鏡觀察中，發現基地中的顆粒內部還有著奈米尺度的黑白夾雜微細顆粒，並且也同樣在718超合金觀察到這一現象，相互應證了合金材料中確實存在此種微觀結構變化。
起初，研究人員認為材料是直接經由序化反應而產生有序相，而在本研究中透過穿透式電子顯微鏡，發現了材料在奈米尺度的微觀現象，經過探討後判斷為材料在相變化過程中，內部會發生連續的spinodal相分離。因此藉由本次研究所觀察到的現象，修正了以往研究人員所認為的材料相變化過程，以及根據此一結果將其繪製成相變化過程示意相圖。希望本次研究能讓未來相關人員對於合金鋼相變化有更進一步的瞭解，並為其提供更深入的研究方向。

Due to the development potential of manganese aluminum alloy steel and the significant role of 718 superalloys in high-temperature structural materials, this paper selects these two alloy materials for research. In this study, we conducted different heat treatments and utilized various instruments to observe and analyze microstructural phase transformations. Remarkably, our TEM observations revealed a previously unexplored phenomenon of nano-scale spinodal decomposition within the matrix in manganese-aluminum alloy steel and 718 superalloys. Initially, researchers believed that the material directly formed the ordered phase through ordering reactions. However, after further investigation through TEM observations at the nano-scale, we discovered that during the phase transformation process, the material undergoes continuous spinodal phase separation, followed by the enrichment of solute phases forming the ordered phase through ordering reactions. Based on the insights gained from this study, we have refined the phase transformation process and proposed an amended phase transformation reaction equation. We anticipate that these findings will significantly contribute to a deeper comprehension of phase transformations in alloy steels for future researchers. Moreover, we hope our results will provide them with more comprehensive research directions.

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