1986 年 52 巻 476 号 p. 862-866
The influence of vacuum environments on near-threshold crack growth behavior in an annealed 60-40 brass have been studied by means of fracture mechanics and fractography. In vacuum, the crack growth rate was smaller than that in air and decreased with decreasing vacuum pressure. When the R ratio and ΔK level increased, the crack growth rate in vacuum approached that in air. The near-threshold crack growth behavior in vacuum was markedly influenced by a fracture roughness, which resulted from a crystalline fracture mode, in addition to a plastic induced crack closure.