Accession Number:

ADA123403

Title:

Mechanical Properties of Adhesively Bonded Aluminum Structures Protected with Hydration Inhibitors,

Descriptive Note:

Second year rept.,

Corporate Author:

MARTIN MARIETTA LABS BALTIMORE MD

Report Date:

1982-11-01

Pagination or Media Count:

41.0

Abstract:

Research has shown that an adsorbed monolayer of the organic inhibitor nitrilotris methylene phosphonic acid NTMP improves the bond durability of 2024 Al adherends prepared by phosphoric acid anodization PAA. As had previously been determined for Forest Products Laboratories FPL-prepared adherends, maximum improvements in bond durability occurred when a monolayer of NTMP was adsorbed onto the surface. Examination of the wedge test failure surfaces of PAA adherends treated in NTMP revealed that although crack propagation had initially involved oxide-hydroxide conversion of the original PAA oxide, the locus of failure transfers to the adhesive near the interface quite early in the test. This means that the failure of NTMP-treated PAA adherends was predominantly cohesive through the adhesive. In addition, the presence of NTMP at the oxideadhesive interface did not degrade the initial bond strength when epoxy-based adhesive systems were used. Author

Subject Categories:

  • Adhesives, Seals and Binders
  • Metallurgy and Metallography
  • Mechanics

Distribution Statement:

APPROVED FOR PUBLIC RELEASE