32 nd International Field Emission Symposium / 32ème Symposium International d'Emission de Champ
J. Phys. Colloques 47 (1986) C2-245-C2-250
DOI: 10.1051/jphyscol:1986237
THE QUANTITATIVE ANALYSIS OF COPPER IN IRON BASED ALLOYS
G.M. WORRALL et G.D.W. SMITHDepartment of Metallurgy and Science of Materials, University of Oxford, Parks Road, GB-Oxford OX1 3PH, Great Britain
Abstract
The quantitative analysis of low copper levels in iron based alloys has been investigated using the Oxford VG FIM 100 atom probe, in particular the optimum experimental conditions necessary to give the correct stoichiometry. Variables investigated include pulse fraction, specimen temperature, crystallographic plane, the presence of image gas and the effect of laser-pulses compared to voltage-pulses. Careful control of certain experimental conditions, especially temperature and pulse fraction, is necessary to give the correct copper level. These results are being applied to an investigation of the role of copper in the embrittlement of low alloy steels.