925 Industrial Drive South
Sauk Rapids, MN 56379

engelmet@engelmet.com

Scanning Electron Microscopy/Energy Dispersive Spectroscopy

• Hitachi 3200N (SEM) and Noran Voyager III (EDS)
• Microstructural evaluations
• Fractographic examinations
• Natural state observations (coating not required)
• Wet/oily specimen observation
• Qualitative and semi-quantitative analyses
• Microimaging
• Light element detection
• Selected area x-ray mapping
• Elimination of elemental interference through peak shape analysis

The SEM is one of the major tools in the failure analysis process. After initial visual examination of the specimen, the sequence of procedures for a SEM examination in a typical project might go as follows:

• Failure area viewed at low magnification -secondary electrons show an overall picture of the area.
• Magnification increased to about 300X- secondary electron view highlights details with excellent depth of field.
• Magnification increased to 3000X- backscatter electrons used to examine grain structure.
• EDS system identifies the elements present and their percentages in the materials examined.

EDS Spectrum

150X

200X

Newer is Better!

Conventional SEMs use high vacuum to achieve the the clean environment needed to examine objects at high magnifications.

The new SEMs can operate in a second mode-variable pressure. This allows specimens to be examined in their natural state. This is a terrific improvement because it eliminates the need for drying or coating.

Sugar crystal 250X
High Vacuum

Sugar crystal 250X
Variable Pressure