Continuous-wave ultrasound reflectometry for surface roughness imaging applications

F. G. Mitri, R. R. Kinnick, J. F. Greenleaf, M. Fatemi

Research output: Contribution to journalArticlepeer-review

14 Scopus citations


Background: Measurement of surface roughness irregularities that result from various sources such as manufacturing processes, surface damage, and corrosion, is an important indicator of product quality for many nondestructive testing (NDT) industries. Many techniques exist, however because of their qualitative, time-consuming and direct-contact modes, it is of some importance to work out new experimental methods and efficient tools for quantitative estimation of surface roughness. Objective and method: Here we present continuous-wave ultrasound reflectometry (CWUR) as a novel nondestructive modality for imaging and measuring surface roughness in a non-contact mode. In CWUR, voltage variations due to phase shifts in the reflected ultrasound waves are recorded and processed to form an image of surface roughness. Results: An acrylic test block with surface irregularities ranging from 4.22 μm to 19.05 μm as measured by a coordinate measuring machine (CMM), is scanned by an ultrasound transducer having a diameter of 45 mm, a focal distance of 70 mm, and a central frequency of 3 MHz. It is shown that CWUR technique gives very good agreement with the results obtained through CMM inasmuch as the maximum average percent error is around 11.5%. Conclusion: Images obtained here demonstrate that CWUR may be used as a powerful non-contact and quantitative tool for nondestructive inspection and imaging of surface irregularities at the micron-size level with an average error of less than 11.5%.

Original languageEnglish (US)
Pages (from-to)10-14
Number of pages5
Issue number1
StatePublished - Jan 2009


  • Continuous-wave
  • Nondestructive imaging
  • Phase
  • Reflectometry
  • Surface roughness imaging
  • Ultrasound

ASJC Scopus subject areas

  • Acoustics and Ultrasonics


Dive into the research topics of 'Continuous-wave ultrasound reflectometry for surface roughness imaging applications'. Together they form a unique fingerprint.

Cite this