Comparison of Lattice Parameter and Resistivity Change in Electron‐Irradiated Copper

Lattice parameter and residual resistivity measurements were performed on high‐purity copper samples irradiated simultaneously with 2.6 MeV electrons at 6 K up to defect concentrations of about 0.1%. Lattice parameter changes could be measured with a resolution of Δa/a = 5 × 10 −6 . In six irradiations the ration η = (Δa/a)/Δϱ was determined as a function of defect concentration and thermal recovery. During defect production the ratio η amounts to (1.75 ± 0.10) × 10 3 (Ωcm) −1 and is independent of the defect concentration. Furthermore, the ratio η stays constant throughout the recovery stages I, II, and III.