12 Bicycle Metals

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Bicycle Metals by ELLEN B. CUTLER

Chapter 1 What Are Metals? Metals are a solid. A solid has a shape of its own. Most solids do not bend. They break. Yet metals are different from most solids. Metals can bend. We can also change the shape of metal. We do this by making the metal very hot. Very hot metal turns into liquid. Liquid metal can be made into different shapes.

Chapter 2 Strong and Light There are many strong metals. Some of them are heavy. Some of them are light. What kind of metal would you use to make a bicycle? You would want a strong, light metal. Strong metals keep a bicycle from breaking or bending. Light metals make a bicycle easier to ride. They make it easier to lift, too.

Chapter 3 Changing What a Metal Can Do Most of the metals we use are metal mixtures. Some mixtures are made of two or more metals. Other mixtures are made of metal and other materials. All these mixtures are melted together. A mixture made from heavy materials can be light! A mixture made from soft materials can be strong!

Chapter 4 Aluminum and Aluminum Mixtures We use metals and metal mixtures every day. One kind of metal is aluminum (uh-LEW-muh-nuhm). Aluminum foil is a thin sheet of metal. It bends easily. People use aluminum foil for cooking and wrapping food. Aluminum mixtures are used to make buildings and bridges. They are also used to make bicycles.