About amntl:

Major activities in this laboratory include both basic R&D and applied research in the field of Microwave and Millimeter Wave Nondestructive Testing and Evaluation, covering the frequency range of 1 GHz – 150 GHz. Examples of recent investigations and developments are:

  • Detection and sizing of small changes (in the few micrometer range) in dielectric sheet materials, such as polymers, coatings, ceramics and thermal barrier coatings,
  • Porosity estimation in composites and ceramics such as thermal barrier coatings and composite skin subjected to loading (i.e., aircraft radome skin),
  • Detection and estimation of void and delamination within sandwich composites such as aircraft radomes, thermal insulation materials such as spray on foam insulation (SOFI) and acreage heat tiles,
  • Detection of internal flaws, defects and moisture permeation in thick composites including honeycomb structures used in aircraft radomes and SOFI,
  • Fatigue crack detection and sizing on metal surfaces, using three distinct approaches,
  • Detection of surface anomalies in metals (i.e., rolled),
  • Cure state monitoring of various chemically produced materials (i.e., resin binder, rubber, etc.),
  • Detection and evaluation of corrosion (including corrosion precursor pitting) under paint and composite laminates,
  • Cure-state monitoring in resins, rubber products and cement-based materials (i.e., cement paste, mortar and concrete),
  • Determination of water-to-cement ratio (w/c) in fresh cement paste, mortar and concrete,
  • Determination of water-to-cement ratio (w/c) in hardened (cured) cement paste, mortar and concrete,
  • Determination of sand-to-cement ratio (s/c) in mortar,
  • Determination of coarse aggregate-to-cement ratio (ca/c) in concrete,
  • Evaluation of aggregate segregation in concrete,
  • Detection of grout-filled cells in masonry blocks,
  • Evaluation of concrete compressive strength,
  • Evaluation of porosity in mortar,
  • Detection and evaluation of chloride added to the mixing water of cement-based materials,
  • Detection of cyclical chloride ingress in mortar,
  • Detection and evaluation of alkali-silica reaction (ASR) gel in concrete,
  • Microwave thermography,
  • Detection and sizing of delamination between FRP composites and cement-based materials such as CFRP-strengthened bridge concrete bridge members,
  • Development of hybrid measurement technique using embedded modulated scattering PIN diode-loaded dipole antenna for material characterization and microwave imaging,
  • Near-field high-resolution imaging,
  • Development of synthetic aperture-focused (SAF) and holographical or 3-D imaging of interior of composites and objects,
  • Development of rapid imaging systems using coherent transceivers and rotary scanning platforms,
  • Development of real-time, 3D, portable, battery-operated and high-resolution imaging techniques/systems,
  • Development of frequency-modulated continuous-wave (FM-CW) radar for short-range applications such as detection and evaluation of flaws in composite structures (e.g., walls).
  • Development of robust microwave and millimeter wave testing and imaging systems for specific applications,
  • Microwave and millimeter wave noninvasive diagnosis of human skin for cancer and burns, and
  • New applications being discovered continuously.


The amntl is fully equipped with microwave and millimeter wave equipment including sweep oscillators and other solid state generators; vector network analyzers; various waveguide and coaxial components, etc. The amntl also includes a small 50 W microwave thermography system. In addition, the laboratory is equipped with several fully automated and computer-controller 2-D scanning tables for imaging purposes.





Applied Microwave Nondestructive Testing Laboratory (amntl)
210 Engineering Research Laboratory
Rolla, MO 65409-0040


(573) 341-4728


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