Accession Number : AD0765522

Title :   Inelastic Deformation of Metals Under Dynamic Loading.

Descriptive Note : Final rept. 11 May 70-30 Jun 73,

Corporate Author : BROWN UNIV PROVIDENCE R I

Personal Author(s) : Duffy,Jacques W. ; Clifton,Rodney J.

Report Date : 31 JUL 1973

Pagination or Media Count : 4

Abstract : The research is a study of the plastic response of metals to the application of dynamic loads. The study can be divided conveniently into two parts: (a) experiments on short specimens in which the state of stress is essentially homogeneous and (b) wave propagation investigations. A split-Hopkinson bar for bi-axial loading of short specimens (torsion and compression) at equivalent strain rates of about 400 or 500/sec was developed. The influence of annealing temperature on strain rate effects in copper was studied. Experiments were performed on thin-walled tubes of alpha-titanium in which pre-torqued tubes are subjected to an axial imapct. The results of these experiments cannot be explained satisfactorily using a strain rate independent theory. It was found necessary to develop a strain rate dependent theory which then predicted the actual material behavior with good accuracy. (Modified author abstract)

Descriptors :   (*METALS, *DEFORMATION), LOADS(FORCES), DYNAMICS, STRESSES, PROPAGATION, COPPER, TITANIUM

Subject Categories : Metallurgy and Metallography

Distribution Statement : APPROVED FOR PUBLIC RELEASE