THREE YEAR TIDEWATER CORROSION OF ALUMINUM ALLOYS

THE GOOD CORROSION CHARACTERISTICS OF ALUMINUM ALLOYS WERE CONFIRMED BY THE RESULTS OF A TEST PROGRAM INVOLVING EXPOSURES FOR PERIODS UP TO THREE YEARS DURATION IN SEA WATER ENVIRONMENT. THE CORROSION RATES, MEASURED BOTH DEPTH OF PITTING AND BY PROPERTY CHANGES, TEND TO REACH A PLATEAU AFTER ABOUT TWO YEARS AND ARE RELATIVELY CONSTANT THEREAFTER. THE ALLOY SYSTEM OF ALUMINUM HAVING MAGNESIUM AS THE MAJOR COMPONENT SHOWED GOOD CORROSION RESISTANCE IN SEA WATER IMMERSION. THE BARE ALUMINUM-COPPER ALLOYS, 2014 TYPE, AMONG THE STRONGEST OF ALL ALUMINUM ALLOYS, GENERALLY ARE NOT SUITABLE FOR CORROSIVE ENVIRONMENTS, SUCH AS SEA WATER OR SEVERE MARINE ATMOSPHERES. HOWEVER, THE CLADDING OF THESE ALLOYS WITH AN ALLOY SUCH AS 6003 CAN GIVE A COMPOSITE MATERIAL WHICH DEMONSTRATED EXCELLENT CORROSION RESISTANCE, EVEN IN SALT WATER EXPOSURES. THE ALUMINUM ALLOY HAVING MANGANESE AS THE MAJOR ALLOYING ELEMENT HAS GOOD CORROSION RESISTANCE IN MOST NATURAL ENVIRONMENTS. FOR SEA WATER APPLICATIONS, AN ALCLAD 3003 ALLOY IS RECOMMENDED, SINCE DEEP PITTING CAN OCCUR. CORROSION FOR MOST ALUMINUM ALLOYS TAKES THE FORM OF PITTING. WITH THE EXCEPTION OF THE 3003 ALLOY, NO ALUMINUM ALLOY TESTED SHOWED A PIT DEPTH GREATER THAN 11 MILS AFTER THREE YEARS' TIDEWATER IMMERSION. THE COPPER CLAD ALUMINUM ALLOYS WERE SHOWN TO BE UNSUITABLE FOR CORROSIVE ENVIRONMENTS, SINCE THE ALUMINUM WAS ANODICALLY CONSUMED AS A RESULT OF THE PROXIMITY TO THE ROLL BONDED COPPER SHEET. THE LIFE OF THE BARE GALVANIZED SHEET IN TIDEWATER IMMERSION WAS LESS THAN TWO YEARS.

• Availability:
  • Find a library where document is available. Order URL: http://worldcat.org/issn/00281425
• Supplemental Notes:
  • Vol 76, No 3, PP 443-449
• Corporate Authors:

  American Society of Naval Engineers

  Suite 507, 1012 14th Street, NW
  Washington, DC  United States  20005
• Authors:
  • Ailor, W H
  • Reinhart, F M
• Publication Date: 1964-6

Media Info

• Serial:
  • Naval Engineers Journal
  • ISSN: 0028-1425

Subject/Index Terms

• TRT Terms: Aluminum alloys; Cladding; Copper; Corrosion; Corrosion resistance; Corrosion tests; Galvanic corrosion; Immersion tests; Magnesium; Manganese; Pitting; Seawater
• Uncontrolled Terms: Corrosive environments
• Old TRIS Terms: Immersion corrosion tests
• Subject Areas: Geotechnology; Highways; Materials;

Filing Info

• Accession Number: 00216452
• Record Type: Publication
• Files: TRIS
• Created Date: May 24 2003 12:00AM