DID YOU KNOW? DTIC has over 3.5 million final reports on DoD funded research, development, test, and evaluation activities available to our registered users. Click HERE
to register or log in.
RESEARCH DIRECTED TOWARD THE STUDY OF THE RADIATION DAMAGE THRESHOLDS OF THE ELEMENTS
AIR FORCE CAMBRIDGE RESEARCH LABS L G HANSCOM FIELD MASS
The changes in residual electrical resistance produced by bombardment with high energy electrons were measured for a number of metals as a function of electron energy in the range from 0.5 to 1.5 Mev. The irradiations were performed at 20 K and lower and recovery measurements were made up to 300 K. The production curves were analyzed using simple displacement theory and the following values were found for the average threshold energies Al--32 ev Au--greater than 40 ev Ag--28 ev Cu--22 ev Fe--24 ev Mo--37 ev Ni--24 ev Ti--29 ev and W greater than 35 ev. Approximate values for the resistivities of Frenkel pairs in units of microhms cm per atomic per cent were also obtained as follows Al--3.4 Ag--1.4 Cu--1.3 Fe--12.5 Mo--4.5 Ni--3.2, and Ti--42. In the case of Al it was necessary to take secondary defect production into account and a number of representative theoretical curves, based on different assumptions concerning the process of secondary defect production, are included. The behavior of Zn was anomalous in that the added resistivity was not a linear function of electron dose at 20 K. Author