Microwave and millimeter wave nondestructive testing and evaluation

The past two decades have seen an increase in scientific investigation and hardware development in the area of nondestructive testing and evaluation (NDT&E). An overview is given of three recent applications of microwave and millimeter wave NDT&E techniques that involve novel instrumentation development and measurements. The first application is disbond detection in strengthened concrete bridge members retrofitted with carbon fiber reinforced polymer (CFRP) composite laminates. The second is corrosion pitting and precursor pitting detection in painted aluminum and steel substrates. The third and final application is the detection of flaws in spray-on foam insulation and the acreage heat tiles of the Space Shuttle through focused and synthetic imaging techniques. All three examples have been performed at the Applied Microwave Nondestructive Testing Laboratory at the University of Missouri-Rolla.