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20 The PCB Magazine • July 2016 ly is the most important part of a fractographic analysis. All of the important questions about type, initiation point, direction, etc., can all be answered just by looking. The tools which are needed for this type of investigation are com- mon for most laboratories. Simply put, a mi- croscope and a good light source. Stereomicro- scopes are the norm for this type of visual ex- amination as their two-eyepiece design allows for easier inspection of the non-smooth fracture surfaces. Inexpensive, relatively speaking, the stereomicroscope can commonly obtain images of fracture planes, voiding, etc., and provide a good bit of information in a very short time- frame. Taking your inspection to the next level, a scanning electron microscope (SEM) is another great tool for the visual inspection of fracture surfaces. Besides the fact that SEMs take a dif- ferent kind of picture, using it as a visual exami- nation tool, this type of microscope eliminates the potentially biasing visual characteristics of color, sheen, gloss, etc., that may get in the way when viewing your specimens with a tra- ditional stereomicroscope. Visual examination via SEM is a lesson in shades of gray; however, SEEING IS BELIEVING IN FRACTOGRAPHIC ANALYSIS Figure 2: Representative close-up of fracture surface using steromicroscopy. Figure 4: SEM close-up of fracture surface with voiding. Figure 3: Representative SEM overview of fracture surface with voiding. Figure 5: High magnification close-up of repre- sentative fracture surface.