Proton irradiation creep and in-pile creep and growth tests have been conducted on specimens cut from the same rolled and annealed Zircaloy-2 plate. The proton irradiation creep tests were carried out over the following ranges: stress, 0 to 267 MPa; damage rate, 0.15 to 7.0 × 10⁻⁷ dpa/s; temperature, 513 to 613 K; and dose, up to 1.44 dpa.

These data were analyzed in detail on the basis of single variable tests to give a phenomenological equation of the form ˙ϵϒ=˙G+Aσnφmexp(−¯QRTq) where ˙ϵ^T = total strain rate, ˙G = growth rate, σ = applied stress, φ = damage rate, = growth rate, σ = applied stress, φ = damage rate, T = temperature, and A, n, m, Q, R, and q = material parameters.

Over the range studied the stress and damage rate exponents were unity and the temperature dependence was best described with a q-value of 0.5. Longitudinal and transverse specimens exhibited a degree of creep anisotropy.

Additional specimens were reactor preirradiated to a dose of 1.0 dpa and tested in the ion accelerator. The results of these tests were in excellent agreement with the equation.

The in-pile tests were carried out at the following values: stress, 80 and 140 MPa; damage rate, 9.7 × 10⁻⁸ dpa/s; temperature, 543 to 593 K; and dose, up to 1.42 dpa. These tests also gave results that were in good agreement with the prediction of the equation.