Steel Corrosion Detection Technology Using THz Waves: A Field-operable Unit Based on NIST Spectroscopic Technology


Corrosion of steel cost the U.S. several $100B per year. Early detection of this corrosion, most of which is buried under some kind of protective coating like concrete or polymers, would reduce this remediation cost and improve the safety of infrastructure and factories. Current detection methods cannot sense a particular corrosion product, only the presence of something, and especially at early stages when not much corrosion is present. NIST had a Corrosion Detection Innovative Measurement Science project from 2010-2014, in which a 0.1-1 Thz wave technology based on antiferromagnetic resonance (AFMR) detection was successfully developed. Two of the most common iron corrosion products, hematite and goethite, are antiferromagnetic, and thus can be detected by this method: hematite through several centimeters of concrete and goethite through similar or greater thickness polymer layers. This laboratory-based technology needs to be taken to the field in order to have practical commercial use. From talking to government and industry, there is certainly a large need for this technology and apparently a large commercial market exists, too. NIST desires to see this technology commercialized, which involves some technical challenges in translating the laboratory technology into the field. The main technical challenges are probably using real corrosion products, getting enough power through the barrier, especially concrete layers, to see the AFMR, and locally controlling the temperature of the specific material site of interest (where the beam is impacting).

The goal of this subtopic is to demonstrate a field-operable measurement system, using 0.1 - 1 THz waves, using NIST technology, that identifies the presence of the iron corrosion compounds hematite and goethite under a variety of protective coverings, including concrete (hematite) and polymers (hematite and goethite). NIST has demonstrated this technology in the laboratory – the goal is to be able to move this technology into the field for application to corrosion detection problems in factories and physical infrastructure. To be able to detect specific iron corrosion products through protective barriers is an unmet need in the U.S.

Phase I expected results: Demonstration of the feasibility of taking the laboratory-based technology to the field, with identification of the technical problems that need to be solved and the current equipment that is available for doing so. A plan for how the field equipment would be operated and a list of successful sample applications in the laboratory is part of the Phase I expected results.

Phase II expected results: Demonstration, in the field and on an important application, of a portable antiferromagnetic resonance –based THz system for corrosion detection of hematite and goethite. This system should be capable of being commercialized.

NIST may be available to provide technical guidance, comments and advice on design concepts, discussion of technical problems, and previous lab data.

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