Accession Number:

AD0007919

Title:

THE EFFECT OF CUAl2 DISPERSIONS ON THE FATIGUE OF ALUMINUM-COPPER ALLOYS

Descriptive Note:

Technical rept.

Corporate Author:

CALIFORNIA UNIV BERKELEY MATERIALS RESEARCH LAB

Personal Author(s):

Report Date:

1953-04-01

Pagination or Media Count:

30.0

Abstract:

The fatigue properties of Al-Cu alloys containing CuAl sub 2 dispersions were measured at room temperature. The properties were substantially independent of the degree of dispersion the coarser dispersions had slightly higher fatigue strengths. The same dispersions in spheroidal steels exhibit 50 increases in flow stress and endurance limit. A study of the nature of crack formation in the alloys revealed that the nucleation of micro-cracks depended primarily on the critical resolved shear stress on slip planes. Final failure was attributed to the accumulation and coalescence of micro-cracks in the grain- boundary regions. The fatigue properties of the alloys may be improved by the introduction of preferred orientations in which the 111 poles fall outside the regions susceptible to rapid crack nucleation.

Subject Categories:

  • Properties of Metals and Alloys

Distribution Statement:

APPROVED FOR PUBLIC RELEASE