Accession Number : AD0725168

Title :   Slipless Fatigue in Titanium.

Descriptive Note : Technical rept.,

Corporate Author : GEORGE WASHINGTON UNIV WASHINGTON D C INST FOR THE STUDY OF FATIGUE FRACTURE AND STRUCTURAL RELIABILITY

Personal Author(s) : MacDonald,Douglas E. ; Wood,W. A.

Report Date : APR 1971

Pagination or Media Count : 23

Abstract : A study by scanning electron-microscope was made of titanium fatigued by alternating torsion at amplitudes confined to its elastic range. A special point was made of distinguishing between the few plastic grains which even in a nominally elastic range develop slip bands and the remaining elastic grains which show no signs of slip. The fatigue which occurs in the plastic grains was studied by an etching technique and shown to be ineffective in comparison with a shear type of transcrystalline fatigue crack which develops and propagates in the elastic grains. Thus in practice an apparently slipless fatigue is possible, here attributed to conditions which allow the grains to build up bands of excessive strain. (Author)

Descriptors :   (*TITANIUM, FATIGUE(MECHANICS)), CRACKS, FRACTURE(MECHANICS)

Subject Categories : Metallurgy and Metallography

Distribution Statement : APPROVED FOR PUBLIC RELEASE