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International Metalfusion Corporation International MetalFusion Corporation P.O. Box 23279 Houston, TX 77228 MEGA/RUST Tel: 409.515.0532 Fax: 409.419.0762 Presentation www.metalize.net COPPER & COPPER ALLOYS AS A PERSISTENT ANTI-FOULING COATING All pictures property of IMC Reproduction without consent is prohibited © Did you know that all three of the ships used by Christopher Columbus on his first voyage had copper sheathing on their hulls? Because of copper's biocidal properties, copper and copper compounds have been used for centuries for the protection of the hulls of ships. Over the ages two different purposes have been served in copper-based ship hull protection. In early wooden ships, a sheathing of metallic copper was used to protect the timbers from being invaded by shipworms known as teredos - worms that bore into wood and weaken its structure. Simultaneously, copper-sheathed ships were protected from the growth of barnacles and algae that increased the frictional resistance of the water against the hull and slowed the speed of the ship. Shipworms are not a problem in modern steel, aluminum and plastic ship hulls; however, the growth of friction-causing marine organisms is detrimental. Fouling both reduces the speed of the vessel and increases its fuel consumption. It also increases wear on propulsion systems. (a) Fire boat VF 541 launched in November 1984, (b) the Cu-Ni clad steel hull prior to launching, (c) the Cu-Ni clad steel hull after 2.5 months in service in Adriatic, (d) hard shell fouling on the coal tar epoxy coated propeller shaft after 2.5 months in the service in Adriatic. Numerous successful test series have been conducted to verify the possibility of cladding container ships and chemical and oil tankers by cladding rudders and small areas on hulls. The severe test conditions ranged from the impacts and abrasion of Arctic ice, to tropical waters of the Panama Canal. BIOFOULING MASS ON 90-10 Cu-Ni SHEATHED STEEL PILINGS AFTER FIVE AND TEN YEARS Piling kg/m2 Percent Biofouling Organisms Bare Steel* 5 years 18.00 100.0 massive barnacles, oysters, etc. 10 years 12.00 100.0 Concrete-Insulated Cu-Ni on Steel 5 years 0.36 1.9 only scattered barnacles 10 years 0.14 1.2 Cu-Ni Directly Welded to Steel 5 years 7.95 44.3 moderate barnacles, oysters, etc. 10 years 4.43 36.8 Rubber-Insulated Cu-Ni on Steel 5 years 0.26 1.4 scattered barnacles, oysters, etc. 10 years** 0.51 4.2 Rubber-Insulated Cu-Ni on Steel w/Galvanic Couple (single point contact) 5 years 4.59 25.5 moderate barnacles, oysters, 10 years*** 15.39 37.0 *. unsheathed - experimental control **. average value (3 pilings) **. average value (2 pilings Until now…… A study conducted by Perkins and Marsh at Lockheed in California demonstrated that it is technically feasible to arc-spray offshore structures with either copper or 90-10 Cu-Ni. The process can be used to sheath complex shapes including nodes and welds that cannot be sheathed readily with sheet material. Free standing forms of either copper or 90-10 Cu-Ni that replicate a contoured surface can also be arc-sprayed. Both arc-sprayed copper and 90-10 Cu-Ni exhibited parabolic corrosion kinetics in seawater and both showed good resistance to biofouling during a 413-day exposure in San Diego harbor. These initial results show promise but additional experience is needed. Most importantly, the arc-sprayed coating allows non-destructive inspection of the underlying steel for fatigue cracks. IMC is leading the way in thermal spray applications of Copper and Copper/Nickel alloy Weldment repair on steel hull Surface preparation of repaired areas Copper/Nickel being applied Completed application on repaired areas BUOY APPLICATIONS IN THE GULF OF BAHRAIN BUOY APPLICATIONS IN THE PACIFIC Some Advantages of Utilizing The IMC Arc Thermal Spray Copper and Copper/Nickel Applications Instant curing and speedy application, means much less down time and labor cost savings IMC applications utilize only air and electricity in our process No VOCs, solvents or chemicals used No hazardous storage ONLY CERTIFIED COPPER OR COPPER/NICKEL WIRE IS USED IN OUR APPLICATION The IMC ASMM is the next generation of arc thermal spray equipment! It has the capability of spraying any alloy drawn into wire form. The two main copper-nickel alloys have their major applications in marine environments, due to a unique display of two chief properties: corrosion and bio- fouling resistance. Several very successful exercises have also been conducted over recent years with entire ships’ hulls being either fabricated from copper-nickel, or clad with sheets or small platelets. This is seen as an important future market both for leisure and commercial vessels. The experience gained over the past 30 years leads to the following conclusions: The combination of seawater corrosion resistance and a high inherent level of biofouling resistance makes Cu-Ni an ideal material for boat hull applications. Ease of fabrication allows the possibility of solid Cu-Ni or Cu-Ni clad steel hulls, thermal spray applications, welded sheathing or attachment by adhesive backed foil. No coatings and associated maintenance are required. No cathodic protection is required and its absence is necessary to maximize resistance to biofouling. Galvanic considerations need to be observed for hull attachments and fitments. Macrofouling is minimized by regular exposure to open waters. Any fouling colonization occurring usually during extended mooring in quiet conditions, will be loosely attached and easily removed by a light scraping action or by getting underway. Information resource: Copper Development Assoc. Metalizing: Tested and Proven Effective The metalizing process has been tested and proven effective by: • The United States Navy The United States Army Corps of Engineers The Federal Highway Administration American Water Works The American Bureau of Shipping INTERNATIONAL METALFUSION CORPORATION For more information, please contact IMC at: sales@metalize. net Tel: 409.515.0532 Fax: 409.419.0762 www.metalize. net P.O. Box 23279 Houston, TX 77228-3279.
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