Battle of the Beams
Students explore the properties of composites using inexpensive materials and processing techniques. They create beams using Laffy Taffy and water, and a choice of various reinforcements (pasta, rice, candies) and fabricating temperatures. Student groups compete for the highest strength beam. They measure flexure strength with three-point bend tests and calculations. Results are compared and discussed to learn how different materials and reinforcement shapes affect material properties and performance.
Students use taffy to provide a sugar matrix for their own composite beam designs that they test for strength.
While composite materials have been around for decades, they are now heavily researched by materials engineers who design property combinations that are not achievable with monolithic or alloyed materials. New composites are important in aerospace and defense applications in severe engineering environments. Next-generation re-entry vehicles, hypersonic flight applications, ballistics, building construction, material processing equipment, energy and energy production industries are a few applications that use composite materials because of their unique property combinations. Such composites include metal matrix composites, ceramic composites, fiber composites and polymer composites. Within each of these vastly different material systems, material scientists have found unique property behaviors that are somewhat similar. These material behaviors revolve around the reinforcement phase quantity, shape, orientation, size distribution, strength and toughness. Materials engineers and scientists explore these reinforcement quantities, and qualitatively rank them for performance under standardized experimental conditions.
After this activity, students should be able to:
- Explain how composite materials work.
- Use solubility principles to select the best processing temperature to yield optimized sugar solution.
- Describe how composite reinforcements affect material properties.
- Form conclusions based on observations and qualitative assessments.