Apparatus for in situ creep testing during irradiation with high-energy neutrons from a planar neutron source

An apparatus is described for investigating the in situ creep behavior of materials during irradiation with neutrons having a spectrum similar to that of a fusion power reactor. Techniques are discussed for remote, high-vacuum creep testing during irradiation with high-energy neutrons from a planar Be(d,n) source used on the 1.93-m Isochronous Cyclotron at the University of California at Davis. Significant effects of radiation damage on the creep of niobium at a flux of 2 x 10(16) n.m(-2) s(-1) are reported.