本研究旨在加快開發多元素為主的高熵合金，採用相圖計算方法(CALPHAD)搭配高通量技術(High-throughput computation)來模擬鈷-鉻-鐵-鎳-鈦高熵合金在凝固後形成的相結構，並與實驗結合驗證，確認相圖計算方法對高熵合金的可行性及正確性。根據高通量計算，分析了凝固過程中生成FCC單一相的計算結果，本研究把握合金在FCC單相形成區域之顯微結構及機械性質之研究，並希望通過添加少量鈦來提高合金的機械性能，同時觀察鉻含量對合金性能的影響，選擇了三種合金成分比例進行進一步的實驗探究。此外，在高熵合金的研究中，第一原理計算模擬很少與實驗相結合，本實驗針對這一點對合金彈性係數進行模擬實驗。
高熵合金試片使用電弧熔煉方式製備，並對合金進行1000oC的熱處理後淬冷，進行研磨拋光之金相處理，接著對合金做各性質的分析。本實驗分別以掃描式電子顯微鏡搭配能量散射X射線譜(SEM/EDS)觀察顯微結構，並以X光繞射儀(XRD)鑑定合金晶體結構，檢視模擬計算之正確性。由分析結果得知，合金1至合金3皆為FCC的單相結構，實驗結果與計算結果相符合；維氏硬度測試結果顯示，鉻元素的添加有助於硬度的提升，經熱處理的合金3擁有最大硬度488.1 Hv；合金的壓縮特性方面，從合金的應力-應變曲線可以發現合金1至合金3經壓縮後無發生斷裂，顯示出合金優異之塑性。從彈性係數的數據中可發現當鈷-鉻-鐵-鎳-鈦高熵合金中的鉻含量增加，彈性係數與降伏強度隨之增大，其中具有最高彈性係數的合金3代表對於壓縮應力的回復能力最強，有較佳的剛性。而第一原理計算之彈性係數與實驗結果之彈性係數趨勢相同，添加合金之鉻含量，彈性係數隨之提升。
本實驗中，成功使用相圖計算方法設計出以FCC相為主的Co30CrxFe25Ni40-xTi5高熵合金，實驗結果和相圖軟體計算的結果相符合，驗證相圖計算方法對高熵合金的模擬之可行性及正確性，並探討出鉻元素的含量對於其合金系統相結構、硬度及壓縮應力等性質造成的影響。

This study aims to develop multi-element high-entropy alloys more efficiently by combining the CALPHAD method and high-throughput computation. The focus is on simulating the phase structure of Co-Cr-Fe-Ni-Ti high-entropy alloys, and validating the results through experimental analysis. The study investigates the microstructure and mechanical properties of the Co-Cr-Fe-Ni-Ti high-entropy alloys single-phase FCC region, exploring the effects of varying chromium content on alloy performance. Additionally, the study integrates first-principles calculations with experiments to simulate the alloy's elastic modulus.
The high-entropy alloy samples are prepared using arc melting and subjected to heat treatment at 1000°C. Subsequent metallographic treatment is performed for experimental analysis. Microstructures are observed using scanning electron microscopy with energy-dispersive X-ray spectroscopy (SEM/EDS), and crystal structures are identified using X-ray diffraction (XRD) for validation. The results confirm that alloys 1 to 3 exhibit a single-phase FCC structure, with hardness increasing by adding chromium, where alloy 3 achieves the highest hardness. Compressive tests demonstrate excellent plasticity, and the elastic modulus data reveals an increasing trend with higher chromium content.
The study successfully designs Co30CrxFe25Ni40-xTi5 high-entropy alloys dominated by the FCC phase using the phase diagram calculation method. Experimental results align with the computed ones, validating the method's feasibility and accuracy. The influence of chromium content on phase structure, hardness, and compressive stress properties of the alloy system is investigated.

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