Accession Number : AD0733335

Title :   The Effect of Microstructure on Fatigue Crack Propagation in Ti-6Al-6V-2Sn Alloy.

Descriptive Note : Rept. for Sep 70-Jun 71,

Corporate Author : AEROSPACE CORP EL SEGUNDO CALIF LAB OPERATIONS

Personal Author(s) : Amateau,Maurice F. ; Hanna,W. Dave ; Kendall,E. George

Report Date : 20 OCT 1971

Pagination or Media Count : 43

Abstract : The fatigue crack growth behavior of Ti-6Al-6V-2Sn was investigated for five different microstructures, using contoured double-cantilever beam specimens. The fatigue crack growth behavior was compared with the mechanical strength, toughness, and ductility properties for each microstructure. The fatigue fracture suffaces were examined with a scanning electron microscope. Annealed structures consisting of equiaxed primary alpha have the lowest crack growth resistance, while the acicular alpha microstructure resulting from beta annealing has a growth resistance four times greater in the intermediate growth regime. No simple model of crack growth rate using gross mechanical properties describes the relative magnitude nor the ralative order of crack resistance among the different microstructures. (Author)

Descriptors :   (*TITANIUM ALLOYS, CRACK PROPAGATION), MICROSTRUCTURE, FATIGUE(MECHANICS), FRACTOGRAPHY, ALUMINUM ALLOYS, TIN ALLOYS, VANADIUM ALLOYS

Subject Categories : Properties of Metals and Alloys

Distribution Statement : APPROVED FOR PUBLIC RELEASE