本研究利用鑄造方式製備AZ91鎂基複合材料，使用微米MoS2顆粒以及奈米和微米WS2顆粒作為所需添加的強化相，並以攪拌鑄造法的製程將強化相融入AZ91鎂合金中，強化相添加比例分別為0.5wt. %及1 wt. %，之後再對材料進行T4固溶處理，探討添加兩種不同強化相對鎂合金機械性質的影響。
從實驗結果中可以發現添加微米MoS2顆粒以及奈米和微米WS2顆粒能夠有效的達到晶粒細化效果，提升材料之降伏強度及延展性，而其中則以微米0.5wt. % WS2的強化效果最優良，透過T4熱處理能使得β-Mg_17 Al_12相溶解於機材中並析出鋁錳相，該相的析出有助於提升材料之延展性，並且可以從添加微米WS2的鎂基複合材料中發現Mg_2 Si相，此析出物有助於機械性質的提升。

The main purpose of this study is to use AZ91 magnesium alloy as matrix and use WS_2 and MoS2 as the reinforcement particles to produce Magnesium-based composites. In addition, the amount of 0.5, 1 wt.% reinforcement particles were added respectively into matrix by gravity casting. After casting the prepared ingot were used to test the mechanical properties, microstructure. Disscusions of effects about different ratio and reinforcement particles will be included in this study.
From the experimental results it can be found that the grain size tend to decrease compared with the pure magnesium alloys. Due to the grain refinement,the material's Yield strength, ultimate tensile strength and ductily can effectively improve. And the 0.5wt. % WS2 Magnesium-based composites have the best mechanical properties. After T4 heat treatment, the β-Mg_17 Al_12 phase can still found on the Magnesium-based composites, because the AZ91 magnesium alloy has more aluminium inside the alloy, and we can discover some Al-Mn phase, the precipitation of this phase increase the ductility of the material. Also it can be found that Mg_2 Si phase exist in the Magnesium-based composites added by micron WS_2 particles, this precipitations enhance the mechanical properties of the Magnesium-based composites.

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