Metal Surface Examination with the Metallographic Microscope
Most microscopes are advertised as being confined to a life sciences laboratory, where scientists have to keep them upright and under lock and key. You might also be familiar with the sight of scientists using glass slides or placing mere drops of specimens under the microscope. However, the same is not always true in the real world: it is not only the life sciences researchers who can use the microscope, and not all microscopy work requires that specimens be sectioned into thin slices and stained.
Many life science researchers work out in the field, and they need microscopes that will allow them to view specimens even without them having to be sectioned. Moreover, many other researchers, such as those working in engineering and the materials sciences, need microscopes in order to carry out examination work. For instance, materials engineers and metallurgists need the help of a metallographic microscope.
The metallographic microscope is a stereoscopic microscope that has been especially engineered for viewing the surfaces of metals. Such microscopes can have a single eyepiece objective, or be monocular; have two objectives, or be binocular; or have a third hole for fitting in a digital camera, and thus be considered trinocular. It is these trinocular metallographic microscopes that allow the greatest advantage in terms of documentation: because researchers are able to take pictures of their specimens immediately, they can send their results immediately to their superiors, or they can keep their images for retrieval and comparison to new images later.
A metallographic microscope is most commonly used to simply look at metal surfaces at high magnification, and many opaque surfaces, if they are relatively flat, can still be examined. For instance, semiconductor makers and engineers routinely use the metallographic microscope to examine the semiconductor wafers as they pass through quality control. In general, the industrial world makes use of metallographic microscopes to carry out inspection procedures that would otherwise be tedious and unsuccessful had the naked eyes of inspectors been used.
This is not the only use that metallographic microscopes have. In fact, metal surface inspection does not have to be for quality control alone. When metallurgists first study their craft and science, they have to learn how different metals are treated and produced. The different heat treatments that metals have to undergo will manifest in physical deformities or special characteristics of a metal surface. Many metallographic microscopes will come with their own micrometer scales in the eyepieces that will allow these beginner metallurgists to measure the bumps and deformations on the metal surface, and thus be well-versed with the different effects that stress can have on different metals.
There are many different industrial metals that can be observed under the metallographic microscope, and there are many different surface characteristics that can be used to identify the metals or the stress that was placed on them. For instance, copper wires can be used for both laboratory and industrial purposes, but if they are created using sub-standard procedures, they can be brittle and be quite useless. Wrought iron is used for furniture, and it has to attain a certain surface texture in order to be considered fit for use. Other industrially important metals include bronze, steel, and brass, all of which have to be heat treated and examined.
Examining the surface of metals underneath a metallographic microscope also extends to the field of archaeology, where scientists can look at the surfaces of different metals produced in different ages of history. The methods of producing these metals can likewise create different bumps and distortions that scientists can use to make conclusions on how skilful metal workers were during that period of history, and what resources were available for their use. How different civilizations use metals and what kinds of metals they have can also provide a glimpse into the economic situation of that period and what was considered valuable or worthy of exchange.
For instance, metal alloys will look different underneath the microscope. In general, if the alloy contains iron, it might have been created using three different types of iron. Ferritic irons will show up as grains of white with little impurities; phosphoric iron will have large grains; and steel, an iron allow, has regions of dark etches. All these can reveal what procedures the metallurgists of old used in making their alloys, and what technology they had at their disposal to extract iron from ores.
A metallographic microscope is great for many other uses, so if you are interested in exploring the versatility of this tool, look through the online web pages of http://www.metallographic-microscope.com. You will be able to find more metallographic microscopes that can fit your surface examination needs, whether you are conducting your research at an office, laboratory, or classroom. You can also find the best microscope to fit your needs and budget as long as you have a clear idea about what your research will entail, and how much you are willing to spend to conduct and finish it.
