Accession Number : AD0787568

Title :   Test and Exploratory Development of an Optimum Aluminum Alloy Stystem for Ship Structures.

Descriptive Note : Final technical rept. 23 Jun 72-23 Jul 74,

Corporate Author : ALUMINUM CO OF AMERICA ALCOA CENTER PA PHYSICAL METALLURGY DIV

Personal Author(s) : Rogers,Ralph W. , Jr. ; Vernam,William D. ; Shumaker,M. Byron

Report Date : 23 JUL 1974

Pagination or Media Count : 78

Abstract : Evaluation of plate fabricated in the laboratory from a series of Al-Mg alloys having magnesium contents of 7.0 to 9.5% showed an alloy designated as CS19 met the contract requirement of an as-welded yield strength of 30 ksi minimum. Fracture toughness and resistance to general corrosion, to exfoliation and to initiation of stress-corrosion cracks were at least equivalent to present 5456-H116 or H117 alloys. MIG weldments of CS19 plate produced with CS19 electrode and by a practice which provides interpass cooling to 250F were highly resistant to stress-corrosion cracking even after thermal treatment at 212F to simulate metallurgical changes taking place during long periods of service. Nominal composition of CS19 is Al-8.25 Mg-0.4 Mn-0.1 Cr with 0.12 max. Fe and 0.10 max. Si. (Modified author abstract)

Descriptors :   *Aluminum alloys, *Ships, Magnesium alloys, Fracture(Mechanics), Toughness, Stress corrosion, Hardness, Welding, Exfoliation, Manganese

Subject Categories : Properties of Metals and Alloys
      Marine Engineering

Distribution Statement : APPROVED FOR PUBLIC RELEASE