Characterization of Oxide Scales Identification of Oxide Scales - PowerPoint PPT Presentation

Characterization of Oxide Scales

Identification of Oxide Scales • Visual Observation • Optical Microscopy • SEM/EDAX • EPMA • X-Ray Diffraction • AES/ESCA • SIMS

Principle of Optical Microscopy NA – numerical aperture – o.59 for air and 1.5 for Oil Maximum Resolution 2000 A for ordinary lamp and 5000A for halogen Lamp Poor Resolution and depth of Focus

Resolution vs Numerical aperture

Scanning Electron Microscopy Wavelength of ordinary Light – 5000A and that Electron 20 A

Schematic of Scanning Electron Microscope

Scanning Electron Micrograph Showing Surface Morphology of an Oxide

TEM

TEM Micrographs of the Oxide/ Whiskers

Energy Dispersive X-Ray Analysis

Wavelength Dispersive X-rays

Area Mapping of Various Elements in Oxide Scale

X-ray Diffraction

Principle of AES and XPS

Release of Auger Electron from Various atoms

Output of AES