Areas of Interest Include
Metallographic studies are of key significance in the manufacture of basic metals and steel, in the aerospace and automotive industry, in mechanical engineering, construction and in the manufacture of a vast number of industrial and consumer products.
Flexible light and electron microscopes are indispensable features of every metallography lab, whether you develop novel alloy materials or perform quality control to ensure the purity of steel. The measurement of certain parameters like non-metallic inclusion content or grain analysis is specified by strict standards and norms. Metallography is used to investigate metals from copper and titanium to iron, steel and alloys of every description. These investigations are performed quantitatively and reliably using dedicated software modules and automated microscope systems.
The microstructure of metals significantly determines properties such as strength and corrosion resistance. Therefore the detailed investigation of microstructure with the help of microscopy is central to metallurgical disciplines as well as many industrial applications. Features of interest in the metallographic study of microstructure include grain size, grain boundaries, phases, phase transformation and volume fractions, inclusions, morphology and banding.
Basic metals undergo specific treatment in order to prepare them for particular applications and to improve their characteristics, for example by adding alloying elements. In many cases, the microscopy investigation centers on the correlation between the resulting microstructure and the material properties. Microscopical analyses using upright, inverted or polarization microscopes, brightfield and darkfield and also electron microscopes. Each of them play an important part in verifying the effects of treatment and to optimize processing parameters.
Contrast methods of reflected light brightfield result are best suited to analyze the microstructures of etched surfaces. Recognizing grain boundaries, you can draw conclusions on grain sizes, phases and structural constituents. Impurities and structural constituents, such as graphite in cast iron, prior to etching are getting visible. Reflected light darkfield shows up mechanical surface faults such as fracture sites, pores and inclusions as well as cracks, scratches and cavities. Use the polarization contrast to analyze the structure of anisotropic materials, such as magnesium, aluminum, bronze and brass. By using scanning electron microscopes the surface of the metal may or may not be polished and etched, but it must be electrically conductive. Therefore a very thin metallic coating must be applied to non-conductive materials.
Process control in primary metal production also aims to reveal Non-metallic Inclusions in steel (NMI) and contaminants in the material. As such, automated light microscopy analysis allows for a fast and efficient scanning of large sample areas in true color as required by the standards. The rating of non-metallic inclusion content according to standards is possible.
Conspicuous inclusions found during the inspection process can easily be documented in the light microscope and further morphological analysis can be collected in a scanning electron microscope by applying correlative microscopy. This enables high detail structural imaging and precise information about the inclusion‘s chemical composition and crystallographic orientation by X-ray analysis techniques in the SEM like EDS, WDS, or EBSD.