ISSN:
0741-0581
Keywords:
Selective plasma etch
;
Ceramic composites
;
Transmission electron microscopy
;
Life and Medical Sciences
;
Cell & Developmental Biology
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Natural Sciences in General
Notes:
Transmission electron microscopy has been used to isolate and examine the intergranular glass phase in hot-pressed silicon nitride/silicon carbide composites. Previously there have been difficulties in locating a suitable region for studies of this nature because the interfering nitride and carbide grains inhibit isolation of the glass for examination. Radiofrequency plasma etching of thinned sections of 6 wt% Y2O3, 2 wt% A12O3 in Si3N4 containing 30 vol% of SiC proved to be fruitful in isolating the glass phase. A mixture of CF4 and O2 quantitatively remove the acicular nitride phase without any evidence of attack on either the glass or carbide. Composites containing ceria and magnesia as substitutes for yttria behave similarly. This indicates that glasses containing minor to major concentrations of elements forming stable fluorides inhibit the attack of fluoride ions on silica glasses containing these elements.
Additional Material:
5 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/jemt.1060070303