Accession Number : AD0661339

Title :   KINETICS OF FRACTURE.

Descriptive Note : Final rept. Jun 64-Sep 66,

Corporate Author : NEW YORK UNIV N Y RESEARCH DIV

Personal Author(s) : Ezrol,H. ; Margolin,H.

Report Date : SEP 1967

Pagination or Media Count : 46

Abstract : An electronic camera, based on an image convertor tube, has been constructed. The image converter is capable of taking photographs at the rate of 200,000 frames per second. It has been used to study, as a function of temperature, the velocity of fracture in notched zinc single crystals, oriented with the basal plane normal to the axis of tensile impact. At room temperature, cracks will develop and grow at a number of locations, including the notch. As temperature is reduced finally only the crack at the notch propagates. If the highest average velocity among a number of cracks, or in the case of a single crack, the highest average velocity is plotted as a function of temperature, it is found that velocity increases as temperature decreases. Proposed velocity-crack length laws and the data obtained are discussed. (Author)

Descriptors :   (*FRACTURE(MECHANICS), ZINC), (*SINGLE CRYSTALS, *CRACK PROPAGATION), CRACKS, VELOCITY, TEMPERATURE, PHOTOGRAPHY, STRESSES, PHOTOGRAPHS, KINETIC ENERGY

Subject Categories : Metallurgy and Metallography
      Mechanics

Distribution Statement : APPROVED FOR PUBLIC RELEASE