Fracture Toughness
The fracture toughness of advanced ceramics is often measured
using an indentation technique. A polished surface of the material
under test is indented using a Vickers hardness tester, the
cracks which emanate from the corners or the indents are then
measured and provide an indication of the toughness of the material.
Typical microstructures of weak (Fig 1. KIC ~ 3 MPam1/2) and
a tough (Fig 2. KIC ~ 10 MPam1/2) Technox® zirconia are
detailed below:
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| Fig 1. Microstructure of a Low Fracture Toughness advanced
ceramic |
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Fig 2. Microstructure of a High Fracture Toughness advanced
ceramic |
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These values are typical of those obtained from test
pieces and are offered for guidance in the design
of engineering components.
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