DISCUSSION

Session 4 : Water Reactors

Chairman Mr. A.S. Bain

Technical Secretary

Mr. D.A. Howl

M. R. WARREN DANISH ATOMIC ENERGY COMMISSION

Would Mr Aas comment on the relative importance of uniform strain and non-uniform strain in determining failure? After irradiation the uniform strain to failure may be very low (< 1^), of the same order as Mr Aas's generalised failure strain. At the failure point the fracture strain (say 7-10^) must be attained, but the generalised failure strain will be the average strain in the cladding, i.e. the uniform strain. This is an argument that increasing the uniform strain will reduce the number of failures associated with power-ramping.