Preparation of TEM foils from Nb-10 a/o Si.
Ductile phase toughened composites contain phases with significantly different physical properties. Consequently, these phases thin at different rates depending on the sample preparation procedure. A new TEM foil preparation method for the ductile phase toughened Nb-10 a/o Si material has been developed. The method involves chemical thinning in a 70% nitric acid/30% hydrofluoric acid solution followed by electropolishing in a 12.5% sulfuric acid/87.5% methanol electrolyte at -40 degrees C. This procedure for making TEM foils results in large thin areas with the minimum of artifacts. Mechanical grinding of a sample followed by either ion milling, dimpling, or electropolishing produced foils with large electron transparent areas, but with uncharacteristic features of the original Nb-10 a/o Si alloy microstructure. These artifacts were identified as dislocations, surface mottling, and antiphase domains.
Cockeram
B
B
Department of Mechanical and Materials Engineering, Wright State University, Dayton, Ohio 45435.
Jackson
A G
AG
Omlor
R E
RE
Srinivasan
R
R
Weiss
I
I
D000497:Alloys; D008854:Microscopy, Electron / Q000379:methods*; D009556:Niobium; D012825:Silicon
D000497:Alloys; D009556:Niobium; D012825:Silicon