本研究使用AZ91鎂合金作為基材， Al0.5CoCrFeNi2高熵粉末為強化相，以熱壓粉末冶金的方式製造鎂基複合材料。實驗中在AZ91合金中摻雜5 wt. %、10 wt. %、15 wt. %及30 wt. %的高熵粉末(粒徑為10 μm)，探討摻雜量對合金強度的影響；本研究也使用10 μm及90 μm之高熵粉末(摻雜量固定為10 % wt. %)，探討粉末粒徑對AZ91合金硬度的影響。
結果顯示，不同摻雜量之Al0.5CoCrFeNi2高熵粉末鎂基複合材料，其組成均為α-Mg、Mg17Al12、Al-Mn析出物和Al0.5CoCrFeNi2。粉末冶金過程中並未使AZ91與高熵粉末產生相變化。壓縮測試結果顯示，摻雜5 % 10 μm之高熵粉末，使極限抗壓強度45.73 MPa之AZ91增強至150.45 MPa。硬度測驗結果表明摻雜高熵粉末之複合材料硬度皆有增強之效果，摻雜粒徑10 μm高熵粉末之複合材料硬度由55.4HV增強至139.3HV，而摻雜90 μm高熵粉末之AZ91硬度低於摻雜10 μm高熵粉末之AZ91，其硬度為108.6HV。

In this study, 10 wt. % of Al0.5CoCrFeNi2 high entropy powder with the size of 10 μm and 90 μm were added to AZ91 alloy by powder metallurgy. According to the result of hardness and compression strength, particle size of 10 μm was the best candidate. Magnesium-based composites were then fabricated with four different addition amount (5 wt. %, 10 wt. %, 15 wt. %, 30 wt. %) to study the effect. The analysis was then carried out using SEM, XRD, MTS dynamic testing and Vickers hardness.
The experimental results showed that the phase composition of magnesium-based composites with different addition amounts are composed of α-Mg, Mg17Al12, Al-Mn precipitates and Al0.5CoCrFeNi2. The microscopic results show that the high entropy powder did not change the phase structure within the composite during the powder metallurgy process. In the compression test results, addition of 5wt. % 10 μm will increase the maximum compressive strength and yield strength from 45.73MPa to 150.45Mpa and 42.5MPa to 149.9Mpa, respectively. The hardness test showed that the hardness of the composite with high entropy powder were enhanced. The hardness of adding 10 μm is enhanced from 55.4 HV to 139.3 HV, while the addition of 90 μm result the lower hardness of 108.6HV.

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