Through the following key select activities, students study the science of compacting ultra small ceramic particles. They evaluate the evolution of density and microstructure of ceramics as they are synthesized at high temperatures. They then use ceramics to make a voltage-protecting device.
MWM will give students an opportunity to understand the world around them in a way they have never experienced before. The modules promote an awareness of the roles science and technology play in society and guide students to take increased control of their work.
Activity 5: Sintering Ceramics
In Part A, students use a soap bubble model to simulate growth of grains during firing. After firing green bodies in a kiln, students complete Part B by measuring fired density and shrinkage. They discover how firing the ceramic turns a weak, soft, porous object into a dense, strong solid.
Activity 6: Making a Varistor
Students apply electrodes to fired ZnO disks from Activity 5 to make an electronic ceramic device. From their measurements, students find that bismuth-doped ZnO displays a variable resistance with applied voltage.
Design Project 1: Designing a Low-Clamping Voltage Suppressor
Students create a low-threshold-voltage varistor based on bismuth-doped ZnO powder. They systematically test three prototypes of the varistor and analyze the effect of varying a single design parameter on the overall performance of the varistor.
Connecting to Your Curriculum
Materials World Modules are simple to organize and inexpensive to run. They are designed to be easily incorporated into any middle school science or high school science lab or lecture course. The chart below lists the subjects covered in the Activities and Design Projects sections of this module.
Physics & Physical Science
Geology & Earth Science
Biology & Life Science