Accession Number : AD0764241

Title :   Hydrostatic Pressure Induced Ductility Transitions in Pure Bismuth and Tin-Bismuth Alloys.

Descriptive Note : Technical rept.,

Corporate Author : WATERVLIET ARSENAL N Y

Personal Author(s) : Dembowski,P. V. ; Pepe,J. ; Davidson,T. E.

Report Date : JUN 1973

Pagination or Media Count : 48

Abstract : The mechanical behavior of pure (99.999%) bismuth and tin-bismuth alloys of various compositions has been observed over a range of superimposed hydrostatic pressures. Results indicate that maxima in ductility (as measured by percent reduction in area at the fracture surface) in specimens tested at atmospheric pressure occur at compositions bordering pure tin and the eutectic composition. At sufficiently high pressures all compositions failed by rupture, i.e. necking to virtually 100% RA. For pure bismuth, pressure was observed to retard failure due to the formation of cracks at twin-grain boundary intersections; this result was consistent with the hypothesis that the effect of pressure is to shift the mode of crack propagation by decreasing the normal tensile component of stress acting on a crack. (Author)

Descriptors :   (*BISMUTH, MECHANICAL PROPERTIES), (*BISMUTH ALLOYS, MECHANICAL PROPERTIES), (*TIN ALLOYS, MECHANICAL PROPERTIES), INTERMETALLIC COMPOUNDS, HYDROSTATIC PRESSURE, LOADS(FORCES), DUCTILITY, BRITTLENESS, FRACTURE(MECHANICS), CRACK PROPAGATION, TENSILE PROPERTIES

Subject Categories : Metallurgy and Metallography

Distribution Statement : APPROVED FOR PUBLIC RELEASE