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計算力學方法在模擬高爐煉鐵和先進鑄造過程中至關重要。顆粒離散元素法(DEM)是一種計算力學方法，旨在透過模擬顆粒形狀效應和顆粒間接觸來捕捉顆粒材料的流變行為。我們使用計算流體力學(CFD)來與DEM耦合，以合理預測氣體壓力作用下焦炭產生的風徑區及流場動態。同時，DEM也用於捕捉半固態合金在外部負載下的流變行為。上述模擬都有設計對標實驗可資驗證。

Computational mechanics approaches are essential in modeling ironmaking blast furnaces and advanced casting processes. The particulate discrete element method (DEM) is a computational mechanics approach aimed at capturing the rheological behavior of granular materials by modeling particle shape effects and interparticle contacts. We utilize CFD-DEM coupling to reasonably predict the raceway generated by the gas pressure acting on cokes and the associated flow field. Meanwhile, DEM is employed to capture the rheology of semi-solid alloys in response to external loading.

金屬凝固微結構由於會大幅影響材料後續的可加工性、可熱處理性以及各類物化特性，故藉由合適的合金成分和製程參數組合控制金屬凝固微結構是重要的研究工作。本實驗室除了利用顯微鏡分析技術解析先進合金在不同製程參數下基材與第二相形貌、尺寸和種類之外，也結合相場模擬以及同步輻射X光斷層掃描等新興技術，幫助直接描述凝固組織的產生以及演進。

Since the metal solidification microstructure will significantly affect the subsequent processing, heat-treatment characteristics, and other physical and chemical properties of the material, it is essential to control the metal solidification microstructure with a proper combination of alloy composition and process parameters. In addition to a comprehensive analysis of morphology (i.e., type, size, and shape) of the matrix and secondary phases using electron microscopes, we utilize emerging analysis approaches such as phase-field simulation and synchrotron X-ray tomography to help directly describe solidification microstructure developments.

實驗室利用計算相圖軟體以及鎂基&鋁基金屬熱力學數據庫，得以預測輕金屬在環境和合金成分變動時，可能產生的各相種類、含量及其他熱力學物理性質。再者，比較平衡/非平衡凝固條件下固相分率曲線的變異，在比對實驗量測合金凝固路徑以及評估熱裂敏感性至關重要。更近期計算相圖軟體延伸發展的動力學模組，則對於預測擴散型相變態和合金擴散動力學行為非常有用。

We utilize computational phase diagram (CALPHAD) software with thermodynamic databases to predict the type/amount of phases and other physical properties of light metals as a function of operating conditions and alloy compositions. Furthermore, the variation of the calculated solidification curves under equilibrium or non-equilibrium conditions can be compared with measured solidification paths, which is crucial to evaluate the susceptibility of the solidification defects. More recently, the mobility module in the CALPHAD software has been applied to predict diffusional phase transformation and the diffusion kinetics of multi-component alloys during thermal processing.

金屬材料適度的晶粒細化有助於增加材料的強度和韌性，同時輕金屬內奈米析出物的尺寸與分布也會顯著影響材料機械性能，是故需要高倍率的電子顯微鏡加以觀察次微米以及奈米組織，以利釐清差排滑移受阻礙的各種因素。本實驗室優化高精度分析試片的製備技術，並用材料系和國科會管理的各式貴儀獲得先進合金內部微細基材組織&析出物的影像以及合金元素分布。

The proper grain-size reduction can increase the strength and toughness of metals, and the size and distribution of nanoscale precipitates in light metals will also significantly affect their mechanical properties. Therefore, high-magnification electron microscopes are required to observe sub-micron and nanoscale microstructures to help clarify the various factors that hinder dislocation movements. We optimize the preparation procedures for high-precision specimens and use different high-valued instruments managed by NTU-MSE and NSTC to obtain microscopic images showing present phases and the distribution of alloying elements in the advanced alloys.