In many industrial materials and consumer products the presence of an unidentified contaminant or foreign substance can be very costly. The contaminant may only be a visual imperfection or in more serious cases it can result in material failure, product recall and potential litigation.

FORAY Laboratories can identify contaminants, while CETEC, using the laboratory results, can investigate the broader problem and assist with solutions.

CETEC in conjunction with FORAY Laboratories has a wide range of techniques to assist in the identification of contaminants. One very successful technique is Scanning Electron Microscope (SEM) which creates magnified images by using electrons instead of light waves. SEM provides much higher magnification than a conventional light microscope to reveal far greater detail.

Also SEM allows the use of back-scattering techniques to highlight the in-homogeneity in the sample (refer to the two images below). Elemental analysis of a selected area of a sample is possible by Energy Dispersive X-Ray MicroAnalysis (EDXA). The EDXA technique is semi-quantitative for elements of atomic number above boron.

Typical problems investigated by SEM/EDXA include:

• Identification of foreign metal fragments in plastic component.
• Measurement and imagery of the topography of etched metal plates as a product development assessment. The magnification level of SEM allows for measurement down to the micron level with the suitable preparation of cross-sectional samples.
• Identification of dark marks on the inside of a beverage container.