Accession Number : AD0682228

Title :   STRESS-CORROSION OF THE ALUMINUM ALLOY 7075-T651 IN ORGANIC LIQUIDS.

Descriptive Note : Final rept.,

Corporate Author : CARNEGIE-MELLON UNIV PITTSBURGH PA DEPT OF METALLURGY AND MATERIALS SCIENCE

Personal Author(s) : Procter,R. P. M. ; Paxton,H. W.

Report Date : SEP 1968

Pagination or Media Count : 50

Abstract : It was shown that stress-corrosion cracks will propagate from a fatigue-precrack in 7075-T651 aluminum alloy exposed to various organic environments; stress-corrosion cracks will not, however, initiate in smooth specimens. Evidence is presented which indicates that the crack propagation is probably not due to traces of water absorbed in the oxide film at the crack tip or in the environments. The stress-corrosion crack growth rate was measured in ethanol and carbon tetrachloride as a function of the plane-strain stress-intensity factor K. The results of a fractographic analysis of the fracture surfaces are described. Evidence is presented to show that some limited dissolution of aluminum in the environments occurs and it is suggested that, as with aqueous stress-corrosion of aluminum alloys, an electrochemical reaction is involved in the cracking. (Author)

Descriptors :   (*ALUMINUM ALLOYS, CRACK PROPAGATION), (*CRACK PROPAGATION, *STRESS CORROSION), FATIGUE(MECHANICS), SURFACE PROPERTIES, MOISTURE, FILMS, OXIDES, ELECTROCHEMISTRY, FRACTOGRAPHY, LOADS(FORCES), ETHANOLS, CARBON TETRACHLORIDE

Subject Categories : Properties of Metals and Alloys
      Fabrication Metallurgy
      Mechanics

Distribution Statement : APPROVED FOR PUBLIC RELEASE