在此篇研究中，利用氣體霧化法制備AlCoCrFeNi高熵合金粉末取代傳統的球磨法，並利用各種儀器，如X光繞射儀(XRD)、場發射掃描式電子顯微鏡(SEM)、示差掃描熱卡量計(DSC)及奈米壓痕儀，探討退火溫度對於晶體結構、微觀結構、相變化及機械性質的影響，此等原子比高熵合金粉末因為快速冷卻的原因，使其擁有初始相純BCC，而不是文獻中提及的雙相結構BCC+FCC，藉由DSC結果能夠發現居禮溫度大約發生在600℃，並於此處發生了相變化，故可以利用退火熱處理使其轉變為FCC相，進而達到相控制的目的，對應XRD分析，此合金系統當熱處理溫度到達600℃時，BCC相開始轉變為FCC相，且越高的溫度所得到的FCC峰值也越高，除了溫度對熱處理有影響外，時間對於FCC相的飽和狀態也有影響，越久的退火時間，能夠使FCC持續成長至一定的程度，而且每個退火溫度的飽和峰值不同，藉由EDS分析，退火後的粉末能夠分為兩部分，一個是富含Cr金屬的區域，另一個則是Al及Ni一同析出的區域，此兩個區代表著不同的相組成，利用EBSD對此合金粉末做相鑑定，發現此合金退火後為BCC (FeCo)、FCC (AlNi3)及σ (Fe0.5Cr0.5)三種相結構組成，故其擁有相異的機械性質，此研究將對其做個別的探討，而熱處理時間對於微觀硬度及相飽和的影響也會在此篇研究中做探討。

In this study, the AlCoCrFeNi high entropy alloy powder was prepared by gas atomization process instead of ball milling method and influences of annealing temperature on the crystal structure, microstructure, phase transformation and mechanical properties using XRD, SEM, DSC and nanoindenter were investigated. From DSC data, it was observed a Curie temperature about 600℃, suggesting that the point occurs phase transition. This equatomic HEAs powder has initial phase: BCC while the FCC phase can be adjusted via annealing treatment. It can be found that the FCC phase begin to grow after annealing treatment above 600℃ and the higher the annealing temperature the stronger the FCC phase. We also found each heat treatment temperature has own specific phase-saturated annealing time. Through the EDS analysis, the powder was divided into two groups: Cr rich region and Al-Ni rich region, these two region has different phases and mechanical properties resulting from distinct constituent phase, so the effects of different heat treatment time on micro-hardness and phase-saturated were also discussed.

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