For my teaching ceramics I search for simple experiments

Ceramic Welding Backing | Ceramic Backing Welding| Ceramic Backing Taps

Experiment:
Space shuttle is covered with ceramic cubes, I think mostly silicon dioxide 
(quartz) variants.  Use a blowtorch at one end to get it red hot, and 
discover the other side is still cool to the touch.

What this demonstrates:
Ceramics are typically excellent insulators of both heat and electricity.  
This demonstrates the thermal insulation quality.

Experiment:
Superconductivity.  With a small sample of a superconductor, some liquid 
nitrogen, and a neodymium type magnet, one can levitate the superconductor 
over the magnet demonstrating superconductivity.  (More about the 
experiments can be found on the web doing a search for superconductors.  A 
good site is locating in Oak Ridge National Labs)

What this demonstrates:
Superconductivity.  A relatively new field of ceramics research, 
superconductors are a promising material candidate for power transmission, 
semiconductors, and just about everything else involving electricity.

Experiment:
Three types of alumina (Al2O3) will show varying degrees of light 
transmittance.  The three types are polycrystalline (opaque), high-density 
nonporous polycrystalline (translucent), and single crystal (transparent).

What this demonstrates:
Optical properties and their relationship to scattering centers within 
ceramics.  The polycrystalline alumina has a large degree of porosity, on 
the order of 5%, which acts to scatter the light transmitted through the 
sample.  The nonporous alumina eliminates the small voids which act to 
scatter the light.  The grain boundaries still act as scattering centers, 
however.  Finally, the single crystal sample eliminates the pores and grain 
boundaries, and light is transmitted without scattering.  All of these 
grades of alumina are technically useful, and economics dictate which grade 
to use for each application.

Experiment:
If you have some type of tensile loading device, you could stretch (tensile 
force) and compress (compressive force) a ceramic sample.

What this demonstrates:
Most people are familiar with the brittleness of ceramics, e.g. a dropped 
plate will break, glass windows break when hit, etc.  These are all results 
of tensile forces.  However, ceramics are much stronger when subjected to 
compressive forces.

Some others:
Subject a ruby sample to ultraviolet light.  The ruby appears to fluoresce 
and is the source of emission for ruby lasers.  Another very basic one is 
sandpaper.  Ceramics are the hardest materials on earth, and are used for 
grinding or polishing other materials including metals and wood.

Date: 2023-04-10     hits: 476    Return