Accession Number : AD0270652

Title :   A METHOD FOR DETERMINING SPALLATION CRITERIA IN SOLIDS

Corporate Author : BOEING CO SEATTLE WASH

Personal Author(s) : KELLER,D.V. ; YOUNG,D.M.

Report Date : NOV 1961

Pagination or Media Count : 1

Abstract : A combined theoretical and experimental program was started to provide information on the one-dimensional equation of state of solids under tension and on the correct criteria for spall. The first material studied was Lucite. Electrically exploded foils were used to accelerate thin Lucite plates to high velocity before impact with a Lucite target. Two types of these plate slaps experiments were performed. The first showed that Lucite spallation occurred instantaneously (within 10 to the -7th power sec) upon the attainment of a critical tension. The second determined the depth at which the rarefaction generated as the projectile free surface overtook the head of the shock in the target. Correlation of these experimental results with a finite-difference hydrodynamic code revealed inherent inadequacies in this type of code for treating spall phenomena. A code was therefore written which uses the method of characteristics to solve the hydrodynamic equations for the case of impact of like materials. (Author)

Descriptors :   *ACRYLIC RESINS, *HYPERVELOCITY PROJECTILES, *SPALLATION, HYDRODYNAMICS, IMPACT SHOCK, MATHEMATICAL ANALYSIS, REFLECTION, SHOCK WAVES, STRESSES, TARGETS, THEORY

Distribution Statement : APPROVED FOR PUBLIC RELEASE