Materials in Today's World

Summary and Final Tasks



Composite materials give us the opportunity to combine two (or more) materials to gain the best of both materials. Many composite materials are composed of a dispersed phase which is embedded into a second phase called the matrix. The matrix completely surrounds the dispersed phase and holds them together. Most composites in use today have been created to have improved stiffness, toughness, and ambient and high-temperature strength. In this lesson, a simple scheme for the classification of composite materials which consists of four main divisions: particle-reinforced, fiber-reinforced, structural, and nanocomposites, was presented and defined. Particle reinforced composites have a dispersed phase which consists of particles whose dimensions are approximately the same in all directions. Fiber-reinforced composites have large length-to-diameter ratio particles (fibers) as the dispersive phase. Structural composites are multi-layered and designed to have low densities and high degrees of structural integrity. For nanocomposites, the dimensions of the dispersed phase particles are on the order of nanometers.

Reminder - Complete all of the Lesson 9 tasks!

You have reached the end of Lesson 9! Double-check the to-do list on the Overview page to make sure you have completed all of the activities listed there before you begin Lesson 10.