Christian M. Wichern Ph.D.
Dr. Wichern completed his BS in Mechanical engineering at SUNY Buffalo. After a brief visit to Tokyo University of Agriculture and Technology, he moved on to Colorado School of Mines to complete his MS and PhD in Materials and Metallurgical Engineering. The next stop was the Max Planck Institut fuer Eisenforschung in Duesseldorf, Germany where he began working with the confocal optical metrology instruments from NanoFocus AG. Taking a job with NanoFocus brought him back to the USA where he and NanoFocus eventually joined the Mahr Inc. team in May of 2018.
Surface metrologists are often tasked with measuring surfaces in hard-to-reach locations. Small bore diameters, undercuts, keyways and gears often have surface finish requirements, but they can also be difficult to access – especially with optical surface metrology instruments, which have line of sight requirements. This presentation will review the use of metrology casting materials or replica materials that are used to create high fidelity reproductions of these difficult-to-measure surfaces. These reproductions can then be more easily measured.
One of the uncertainties of this process is how well the castings represent the actual surface. As part of this study, castings of traceable standards and industrial parts were measured alongside the originals. Comparison of the results allows us to draw some important conclusions about this process.