2020 年 84 巻 3 号 p. 109-114
In this study, the effects of carbon nanoparticles fixed to the surfaces of AM60B and AZ91D magnesium alloy chips on the mechanical properties were examined. The manufacture of magnesium-carbon alloy is not easy because carbon does not possess the property of wettability for magnesium. However, magnesium alloy chips fixed to carbon nanoparticles enable magnesium-carbon alloys to be produced by the thixomolding process. Mechanical properties such as the tensile and fatigue strengths were improved by only 0.1 mass％ of the carbon addition because of the decrease in the void and the refinement of crystal grains. In addition, the AZ91D magnesium alloy was proven to be more effective than the AM60B magnesium alloy for the decrease in the void and the refinement of crystal grains by the carbon addition. The aluminum content of the AZ91D magnesium alloy is higher than that of the AM60B alloy. It seems that the void formation is based on the hydrogen by the reaction between aluminum in the magnesium alloy and water. Therefore, the effect of carbon addition on the mechanical properties was dependent on the aluminum content in the magnesium alloys.
