Effect of Al0.5CoCrFeNi2 high entropy alloy particle on strength of AZ91 alloy

• Main Authors: Wen-Wei Huang, 黃文威
• Other Authors: Chun Chiu
• Format: Others
• Language: zh-TW
• Published: 2019
• Online Access: http://ndltd.ncl.edu.tw/handle/48e979

碩士 === 國立臺灣科技大學 === 機械工程系 === 107 === 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.