The Scanning Electron Microscope (SEM) provides several powerful imaging and analytical capabilities. The first is high magnification; 50,000X + compared to the 2000X maximum typical of the best optical microscopes.

The second is its depth of focus; up to 300 times greater compared to optical instruments. When examining irregular surfaces, such as fractures, this critical capability brings both "peaks" and "valleys", as well as the features between them, into focus in a single high magnification image. With these images, fracture mode (ductile, brittle, fatigue, stress corrosion, hydrogen embitterment, etc.) and origin can be determined with certainty, a crucial step in identifying the root cause of material failure.

The third capability requires an additional instrument working in combination with the SEM. This is the EDS, or Energy Dispersive X-Ray Spectrometer. EDS utilizes energy from the SEM's electron beam to perform an elemental chemical analysis of any area, particle or feature within the SEM's image field. With the wide range of magnification available in the SEM, this combination of instrumentation can analyze areas ranging from a five millimeter square to individual features down to one-fifty millionths of an inch in diameter.

Metallurgical Associates, Inc. operates two SEM/EDS facilities in Milwaukee Wisconsin to provide your company with the rapid turnaround of your analytical requirements. Both instruments have large sample chambers (approximately one cubic foot) which offer the ability to analyze relatively large components without sectioning.

• Fracture Origin and Mode Determination in metals, plastics and composites.
• Energy Dispersive X-Ray Microscopy (EDS) for non-destructive elemental analysis of large components, as well as particles as small as 0.1 microns. Identification of Unknown Materials, Plating and Coatings.
• Elemental Mapping by EDS to characterize spatial relationship of compositional variations, inclusions, liquid metal embrittlement, etc.
• Corrosion Root Cause and accelerant source identification.
• Contaminant, Residue and Deposit Composition and source identification.
• Surface Finish Characterization of cylinder bores and honing patterns, polished and electro-polished tubing, ground surfaces, etc.
• Casting Defect Identification and root cause.
• Forging Defect Identification and root cause.
• Wear Characterization and cause.
• Filtered Particle size and composition.