Both carbon-magnesium alloys and aluminum-magnesium alloys are commonly used light alloy materials, but they have some differences: the composition is different: the main components of carbon-magnesium alloys are magnesium, carbon and a small amount of other impurities, while the main components of aluminum-magnesium alloys are A mixture of aluminum, magnesium, and some other elements. Different densities: The density of carbon-magnesium alloys is lighter than that of aluminum-magnesium alloys, so with the same strength and stiffness, carbon-magnesium alloys are lighter in weight. Different corrosion resistance: The corrosion resistance of carbon-magnesium alloys is not as good as that of aluminum-magnesium alloys. Carbon-magnesium alloys are easily oxidized in humid environments and produce white oxides. In terms of firmness, this is determined by the strength and rigidity (resistance to bending, compression, etc.) of the metal. Which one is more robust depends on the specific application environment and standards. Generally speaking, the strength and stiffness of carbon-magnesium alloys are higher than that of aluminum-magnesium alloys, and they are widely used in some fields that require high strength and lightweight, such as aviation and aerospace. Aluminum-magnesium alloys have better corrosion resistance and are widely used in automobiles, high-speed railways and other fields.