Grantee Research Project Results
Final Report: Development of Zinc Coatings on Steel by CermacladTM to Replace Pickling Lines
EPA Contract Number: EPD14013Title: Development of Zinc Coatings on Steel by CermacladTM to Replace Pickling Lines
Investigators: Samant, Dr. Anoop
Small Business: MesoCoat, Inc.
EPA Contact: Richards, April
Phase: I
Project Period: May 1, 2014 through April 30, 2015
Project Amount: $99,939
RFA: Small Business Innovation Research (SBIR) - Phase I (2014) RFA Text | Recipients Lists
Research Category: Small Business Innovation Research (SBIR) , Pollution Prevention/Sustainable Development , SBIR - Nanomaterials
Description:
MesoCoat, Inc. (MesoCoat), proposes developing zinc coatings with excellent corrosion resistance using the company's R&D 100 award-winning CermaCladTM process, which uses a high-density infrared (HDIR) lamp to fuse a uniform layer of metal onto metal surfaces. The substrate surface is prepared by common cleaning and grit blasting methods, and CermaCladTM engineered precursors are applied onto the substrate (base metal) material by slurry deposition. After precursor application, the HDIR lamp is rapidly passed over the cladding precursor, melting it, and thus bonding the cladding/coating to the base metal. The high power density and large area nature of the fusion system enables these claddings to be applied at high rates. The CermaCladTM application process produces smooth surfaces with less dissolution of the base material, highly refined grain size and stronger metallurgical bond (with unprecedented durability and resiliency). CermaClad'sTM uniform fusion process is capable of controlling the phase and microstructure by controlling heat input. Additionally, metal cladding eliminates the use and disposal of Volatile Organic Compounds (VOCs).
MesoCoat's CermaCladTM process will be used to coat the base materials with Zn in order to minimize the detrimental effect on the environment caused by the pickling step in the galvanizing process conventionally used for coating steel parts. Significant amount of acid waste is generated by the galvanizing operation (for example, in the UK, approximately 32,000 tons of acid waste are generated per year). As the pickling baths typically contain of 80-150 g/L FeCl2, 5-150 g/L ZnCl2, and 10-80 g/L HCl, the CermaCladTM process will substantially prevent the release of hazardous chemicals in the environment on such a large scale.
Summary/Accomplishments (Outputs/Outcomes):
Zinc powder was sourced to confirm a suitable supply for the CermaCladTM Zinc process. These powders were evaluated for relative ease in manufacture of an alloy precursor, prior to coating fusion on steel surfaces. The method of experimental test matrices was used to evaluate precursor thickness and composition as well as lamp operation parameters such as atmosphere around the coating sample, applied current, processing speed and distance relative to the lamp heat source. Variation in these parameters yielded significant differences in coating results, including quantity of surface oxides, order of magnitude differences in coating dilution and coating surface defects. Parameters that provided a smooth, defect-free coating surface with low substrate dilution were down-selected. Arc lamp equipment life relative to coating production also was documented. Demonstration plates were produced, some of which were used for mechanical and corrosion testing.
The metallurgy, mechanical properties and corrosion resistance of the demonstration plates were compared with similar plates that had been hot dip galvanized. The sacrificial nature of Zinc in corrosive environments is the primary driver for application of this metal to steel surfaces. Environmental exposure of the Zinc coatings was simulated through accelerated atmospheric corrosion, ASTM B117 Salt Fog testing, of both CermaCladTM Zinc and commercial galvanized plates. Controlled corrosion testing through open circuit potential measurement (OCP), polarization and Tafel analysis according to ASTM G5-94, and electrochemical impedance spectroscopy measurements (EIS) according to ASTM G106-89 were all performed with a 3.5 wt% NaCl solution to provide insight regarding any corrosion mechanism differences between the commercial galvanized coatings and the CermaCladTM Zinc. Of particular concern to sheet galvanizing operations is the ductility of the Zinc coating; thus, the CermaCladTM Zinc coatings were compared to the commercial hot dip galvanized coatings in bending as well as high strain deformation produced from a Rockwell B indenter.
Conclusions:
Precursor composition and thickness was down-selected and lamp processing parameters determined to successfully melt and fuse a thin (0.1 mm) layer of zinc to plain carbon steel surfaces. The coating surface composition contained 2-3 wt% Fe; the corresponding microstructure was evaluated and found similar to commercial hot dip galvanized plates, having significant volume fraction δ-phase encased by solid solution Zinc. Coating adhesion, through bend and Rockwell B hardness testing, was evaluated and the CermaCladTM Zinc coatings behaved similar to commercial galvanized steel coatings. Finally the corrosion resistance, ASTM B117 Salt Fog as well as open circuit potential measurement, polarization and Tafel analysis according to ASTM G5-94, and electrochemical impedance spectroscopy measurements according to ASTM G106-89, were performed on both CermaCladTM Zinc coatings and commercial galvanized coatings. The CermaCladTM Zinc coatings exhibited similar or better corrosion properties than the commercially galvanized steel, surviving 500 hours of ASTM B117 Salt Fog testing. The open circuit potiential (-1.1 V vs SCE), electrochemical impedance (5-50 kΩcm2), Tafel current (2x10-7 to 3x10-6 A/cm2) of the CermaCladTM Zinc and commercial galvanized Zinc coatings are very similar. The metallurgical, mechanical, and corrosion properties of CermaCladTM Zinc coatings are similar to traditional hot dip galvanized coatings.
Commercialization
Foresight Science and Technology Inc. research suggests the overall market for protective coatings and anti-corrosive coatings for steel are quite large. Both the steel industry and the zinc industry have associations performing research and development on improved anticorrosive coatings for steel products. Interviewees in the industrial and academic sectors echo that this market does embrace innovation. Potential markets could include parts too large for dip galvanizing, onsite repairs to large structures such as bridges, or parts that need improved corrosion resistance. Local galvanizers who do not have the capability of coating these parts may be interested in MesoCoat's CermaCladTM technology as an expansion to their platform. Current interests primarily involve evaluating the speed of this technology against current sheet galvanizing lines. MesoCoat also is investigating partnerships with companies that install and sell galvanizing lines as these companies should be involved in designing and installing the next generation zinc coating processes.
MesoCoat's commercialization efforts seek first to partner with a couple of the largest steel companies to test, improve and drive adoption of our technology. MesoCoat has successfully commercialized several of its coatings for the oil and gas, and mining industries by partnering with leading end-users, and intends to accomplish the same result by partnering with leading steel companies.
MesoCoat is a venture-backed nanotechnology materials science company fast becoming a world leader in metal protection and repair through their revolutionary "long life" coating and "high speed" cladding technologies. MesoCoat has been honored by The Wall Street Journal as the #1 Manufacturing Innovation across the globe, by Pipeline Industries Guild as the Top Subsea Pipeline Technology, by Forbes as the #1 Most Promising Material Science Company in the United States, by American Metals Market with the Steel Excellence Award, by Inc. 500 as one of the Fastest Growing Manufacturing Company in the United States and has received numerous other trade, industry and technology awards, including five R&D 100 Awards and a Technology Innovation Award from the National Institute of Standards and Technology. MesoCoat has successfully raised approximately $30 M in equity, non-dilutive, and development funding, and more than $50 M has been invested in product development and testing by federal agencies, national labs and our companies in order to deliver products that offer improved performance over the current state of art. MesoCoat currently operates from multiple locations in the United States and intends to expand global operations in Canada, Southeast Asia, Mexico and South America.
Supplemental Keywords:
zinc carbonate, coating, galvanized steel, pickling line, volatile organic compound, VOCSBIR Phase II:
Development of Zinc Coatings on Steel by CermaCladTM to Replace Galvanizing Pickling LinesThe perspectives, information and conclusions conveyed in research project abstracts, progress reports, final reports, journal abstracts and journal publications convey the viewpoints of the principal investigator and may not represent the views and policies of ORD and EPA. Conclusions drawn by the principal investigators have not been reviewed by the Agency.