Technical Report NTB 87-09

Subcritical crack growth in high-grade alumina for container applications

The subcritical crack growth of a high-grade, 99.9 % alumina ceramic in a concentrated salt solution at 70°C was investigated by lifetime measurements in static bending tests. For crack growth velocities lower than 10-8 m/s, the crack growth velocity – stress intensity factor relationship was found to be a power law with an exponent in the order of 50. The material had an inert bending strength close to 400 MPa. These values of the material parameters qualify the alumina investigated for high-level waste container applications from the point of view of subcritical crack growth.