The temperature dependence of the cyclic creep behavior was studied for a Cu bicrystal which contained dispersed SiO2 particles and a [011] 20° twist boundary. It was found that failure occurred at shorter times with increasing temperature and stress amplitude. The fracture mode of the bicrystals changed sharply from transgranular to intergranular at a critical stress amplitude. The brittle intergranular fracture that occurred below the critical stress amplitude caused a discontinuous life-shortening. The observed fracture-mode change at the critical stress amplitude was explained in terms of grain-boundary sliding and grain-boundary cracking.

Temperature Dependence of Cyclic Creep Behavior of a Cu–SiO2 Bicrystal with a [011] 20° Twist Boundary. H.Miura, T.Sakai, M.Kato: Acta Materialia, 2003, 51[20], 6163-8