| Issue |
J. Phys. Colloques
Volume 47, Number C2, Mars 1986
32 nd International Field Emission Symposium / 32ème Symposium International d'Emission de Champ
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| Page(s) | C2-251 - C2-257 | |
| DOI | https://doi.org/10.1051/jphyscol:1986238 | |
J. Phys. Colloques 47 (1986) C2-251-C2-257
DOI: 10.1051/jphyscol:1986238
TRANSMISSION ELECTRON MICROSCOPE AND ATOM PROBE STUDY OF FERRITIC STEEL WELDS
G. DUBBEN, M.N. CHANDRASEKHARAIAH, J. BEYER et B.H. KOLSTERMaterials Science Section, Department of Mechanical Engineering, Twente University of Technology, NL 7500 AE Enschede, The Netherlands
Abstract
Small amounts of alloying additives to weld materials are known to result in a beneficial effect on the impact and fracture toughness properties. Three welds, with different amounts of Ti and B in ppm level, were examined using the transmission electron microscope (T.E.M.) and the atom probe field-ion microscope techniques. The inclusions and precipitates observed could be classified into three broad groups depending on their size. The largest ones in the micron range could be analysed using the energy dispersive analyser attached to the T.E.M. The medium ones in submicron range were analysed using electron diffraction methods and the smallest ones in the nanometer range could be analysed only with the atom probe. The volume fraction and composition of the precipitates were found to vary with the microstructure and the impact properties of the three welds. An attempt has been made to correlate the composition of the precipitates with Ti and B content.