Accession Number : AD0754538

Title :   Temper Embrittlement in a Thick-Wall Gun Tube Steel.

Descriptive Note : Technical rept.,

Corporate Author : WATERVLIET ARSENAL N Y

Personal Author(s) : DeFries,Richard S.

Report Date : AUG 1972

Pagination or Media Count : 34

Abstract : An investigation was undertaken to determine the reversibility and susceptibility to temper embrittlement in large 3Ni-Cr-Mo alloy gun tube forgings. The effect of time at temperature in the temper-brittle range was determined. In addition, the effect of microstructure on temper embrittlement was also studied. The degree of embrittlement was based on the change in the fracture appearance transition temperature. It was found that the transformation causing embrittlement is a reversible reaction and that tempering a martensitic structure above 1000F produced no embrittlement. Retempering at a lower temperature can cause embrittlement without a significant change in the yield strength or Charpy impact energy. In tempered martensite, the ductile brittle transition appears to be a function of the yield strength. (Author)

Descriptors :   (*STEEL, EMBRITTLEMENT), (*GUN BARRELS, MECHANICAL PROPERTIES), TEMPERING, TRANSITION TEMPERATURE, IMPACT SHOCK, SHOCK RESISTANCE, TENSILE PROPERTIES, DUCTILE BRITTLE TRANSITION, NICKEL ALLOYS, CHROMIUM ALLOYS, MOLYBDENUM ALLOYS

Subject Categories : Metallurgy and Metallography
      Guns

Distribution Statement : APPROVED FOR PUBLIC RELEASE