Technical Report NTB 89-13

Subcritical crack growth in hot-isostatically postcompacted high-grade alumina

The subcritical crack-growth behaviour of natural cracks in a hot isostatically post-compacted high-grade alumina ceramic was tested in a concentrated salt solution at 70°C. The result of static bending tests yielded a crack-growth law that can be described by a power law with an exponent n = 73.5. This high value reflects an excellent resistance to subcritical crack growth. A comparison with Al203-materials investigated earlier has been included.