Microscopy Lab
The tools in Chemir’s Microscopy Laboratory let our chemists evaluate the microstructure of a variety of materials, for materials testing and identification projects. A variety of optical microscopes are used for sample preparation and in failure investigations. We use the Scanning Electron Microscope (SEM), with a capability of up to 300,000x magnification to image fine structures. Secondary and backscattering electron modes gather different types of information about the structure and composition of materials; additionally, backscattering electron mode allows us to image samples of non-conductive material. Non-conductive materials can also be imaged after applying a thin coating (sputtering) of a conductive material. A low vacuum or “environmental” setting allows for the characterization of water-containing samples or grease/cream type samples. The large sample chamber means that we can often insert the entire sample into the microscope, to avoid destructive analysis. We can also measure thicknesses of materials and sizes of particles and fibers.
Understanding the microscopic structure of materials is imperative when performing a failure analysis study. Cross-sectional analysis, epoxy-mounting and polishing of samples, and other sample preparation techniques are useful when studying surfaces of laboratory samples.
The Energy Dispersive X-Ray Analyzer (EDXA) accessory for the SEM will identify the elemental composition of the sample in the SEM. Specific particles may be analyzed to determine the elemental profile. Alternatively, we can map entire surfaces to understand the elemental distribution and determine whether “islands” of contaminants are present in a sample.
Raman Spectroscopy is a compliment to FT-IR spectroscopy; it is very useful in the identification of polymers and inorganic materials and minerals. Our lab’s Raman Spectrometer is portable and has a microscope attachment so we can identify the chemical composition of small particles or small regions on samples. An electronic library of Raman data is used to identify the major component(s) of samples.
