Radiation Enhanced Diffusion Due to Electrons and Protons

IT WAS FOUND THAT THE ORDERING RATE IN COPPER-30 % ZINC ALLOYS IS DETERMINED BY AN INTERSTITIALCY DIFFUSION MECHANISM DURING IRRADIATION WITH HIGH ENERGY PARTICLES AND BY A VACANCY DIFFUSION MECHANISM DURING ANNEALING AFTER QUENCHING.THE MIGRATION ACTIVATION ENERGIES OF INTERSTITIALS AND OF VACANCIES WERE FOUND TO BE E1I(M) = 0.70 EV AND E1V(M) = 1.0 EV, RESPECTIVELY. THE MIGRATION ACTI- VATION ENERGY OF INTERSTITIALS WAS E1I(M) = 0.68 EV FOR AN ELECTRON FLUX OF 0.035 / UACM-2 (2MEV) DECREASING FURTHER TO E1I(M) = 0.58 EV FOR AN ELECTRON FLUX OF 3.5 /UACM-2. THIS LATTER VALUE WAS ALSO OBTAINED FOR A PROTON FLUX OF 9 NACM-2 (17.65 MEV) AND THIS VALUE DECREASES FURTHER INCREASING THE PROTON FLUX. FOR A PROTON FLUX OF 640 NACM-2 A MIGRATION ACTIVATION ENERGY OF E1I(M)= 0.52 EV WAS MEASURED. IN WELL ANNEALED SPECIMENS THE RADIATION INDUCED POINT DEFECTS ANNIHILATE MAINLY BY PAIR RECOMBINATION. FOR SPECIMENS HAVING A THICK- NESS BELOW 0.1 MM AN APPRECIABLE AMOUNT OF RADIATION INDUCED POINT DEFECTS AN- NIHILATE AT THE SURFACE SUCH THAT THE BULK DIFFUSION RATES ARE CONSIDERABLY REDUCEDNA-NOT AVAILABL