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What is the Superplastic Nano-Science Laboratory ?
In daily life we use a variety of ceramic products. A typical example is chinaware. You probably have the experience of breaking them by accident. When hearing the word, "ceramics", you would imagine those which are fragile and easy to break, along with being somewhat harder and more heat-resistant than metals. The advanced engineering ceramics, such as those used in automobile engines, are strong enough. They are, however, still difficult to machine compared with metals and plastics, and then their range of application is limited in the state-of-art technology.
The situation has been gradually changing since 1986. It was discovered at NIRIN that even hard ceramics can be deformed like a chewing gum under some specific conditions. This phenomenon is called "ceramics superplasticity", and is expected as a new forming technology of ceramics in the next generation. This discovery has become a basis for our laboratory.
Our present researches are primarily about the high-temperature deformation behaviors of ceramics including superplasticity and creep performance. A variety of new findings on ceramics deformation has emerged by combining experimental works and computer simulation techniques,
FIGURES: Superplastic deformation of Y-TZP (left, right).
2. Microstructure development in silicon nitride during superplastic deformation.
FIGURE: Microstructures of silicon nitride before/after the deformation.
3. Computer simulation of polycrystalline materials.
FIGURE: Molecular dynamics simulation of zirconia polycrystals.