Accession Number : AD0845586

Title :   Determination of the Yield Point of Brittle Materials by Using High Hydrostatic Pressure,

Corporate Author : FOREIGN TECHNOLOGY DIV WRIGHT-PATTERSON AFB OH

Personal Author(s) : Brandes, Marek

Report Date : 08 MAY 1968

Pagination or Media Count : 16

Abstract : The yield behavior of several brittle materials was investigated in tensile tests under high hydrostatic pressure. It was found that the plastic flow of brittle materials begins at the moment when the hydrostaic pressure reaches the limiting value p sub o = R sub e - R sub o, where R sub e is the yield strength in tension (unattainable under normal conditions) and R sub o is the brittle fracture stress or tensile strength. An experimental determination of the limiting pressure was arrived at by stretching the specimens under various hydrostatic pressures and fixing the value of p sub o at which the stretched specimen started to fracture. The limiting pressure determined in this investigation for cast-iron specimens was p sub o = O. This proves that the yield strength R sub e of cast-iron is equal to the tensile strength. The tested cast-iron specimens started to flow just at the moment of their fracture.

Descriptors :   (*MATERIALS, YIELD POINT), TENSILE PROPERTIES, BRITTLENESS, IRON, CASTINGS, CREEP, HYDROSTATICS, POLAND.

Subject Categories : Metallurgy and Metallography
      Mechanics

Distribution Statement : APPROVED FOR PUBLIC RELEASE