Writer's Insight – Ceramics
There is an increasing demand in our modern world to develop new materials with properties that fit certain requirements. As a result, a branch of science/engineering known as ‘materials science’ has evolved. It investigates the relationship between the structure of materials at the atomic or molecular level and their physical properties at the macroscopic level.
Ceramics is one of the areas of interest to a materials scientist and is the oldest branch of materials science. A ceramic is a non-metallic solid made up of either metal or non-metal compounds that have been heated and cooled. In general, they are hard, corrosion-resistant and brittle. ‘Ceramic’ comes from the Greek word meaning pottery. Ceramics now includes domestic wares, industrial and building products, art objects and advanced ceramics used in engineering and medicine.
Science ideas and concepts
The overarching theme of this context relates to the structure, properties and classification of matter, and these are the key science ideas and concepts identified:
- What are ceramics?: ‘Ceramic’ comes from the Greek word meaning pottery. The clay-based domestic wares, art objects and building products are familiar to us all, but pottery is just one part of the ceramic world. Nowadays, ceramic materials that are not necessarily clay-based have been developed. These advanced ceramics are being increasingly used in high-performance applications in engineering and medicine. This resource looks at the classification of ceramics.
- What is clay?: Since the earliest times, humankind has had a close association with clay. From use as a building material, in pottery and in a multitude of industrial settings, clay is a key ingredient in the material world we live in. Commercially, the most important clays are known as kaolin and bentonite. This resource looks at how clays were formed and their mineral makeup.
- What are minerals?: A mineral is an element or chemical compound, normally crystalline, that is found in rocks or as natural deposits in the Earth’s crust. Minerals are often used in the production of ceramics. This resource investigates the structural features and physical properties of common minerals. The mineral content of rocks is also considered.
- Bone and tooth minerals: The minerals found in human teeth and bones that give them their hardness and strength belong to a mineral family known as biological apatites. The biological apatites are forms of calcium hydroxyapatite, which has the formula Ca10(PO4)6(OH)2. This resource looks at the chemical and physical properties of this mineral as found in tooth enamel, dentine and bone.
- Temperature – the highs and lows: Advanced ceramic materials are produced from powders heated to very high temperatures. The process is called ‘sintering’. For ceramic superconductors to operate effectively, they need to be cooled to very low temperatures known as the ‘critical temperature’. This resource looks at temperature, temperature scales, and the highs and lows required in the advanced ceramic field.
The context links to these requirements in the curriculum:
- Material World – levels 4–5: Linking the properties of different groups of substances to the way they are used in society or occur in nature.
- Physical World – level 5: Explore a technological or biological application of physics.
The context provides an opportunity to ‘capture’ arts-oriented students as it provides a link into the world of pottery by delving into the ‘old’ world of clay-based ceramics and the ‘new’ world of advanced ceramics.
New Zealand research
These research areas from the advanced ceramic arena add interest to the context:
- Dr Michael Mucalo (University of Waikato) and cow bone-derived hydroxyapatite for use in orthopaedic surgery.
- Dr Nick Strickland (IRL Wellington) investigating the use of ceramics (BSCCO-2223) in superconductive wires.
- Dr Ian Brown (IRL Wellington) investigating the development of advanced ceramics (sialons) for use in metal production and processing industries.
This is cutting-edge research that incorporates the science ideas explored in the context. The video clips of the scientists explaining aspects of their work and research programmes add interest and the ‘human’ side of science to the context.
Teaching and learning activities
The activities have been developed to highlight the science ideas and concepts and focus on the structure, properties and classification of matter. Some relate directly to the research stories.