繰返し応力によって7-3黄銅が受ける被害について

概要

論文の詳細を見る
The nature of the fatigue damage of 7-3 brass specimens is quite the same as what occurs in 6-4 brass or in low carbon steel specimens. The damage is confined within a thin surface layer of the specimen and cannot be removed by stress relief annealing. The thickness of the damaged layer becomes greater when the applied stress is high and the number of the stress repetitions is large. The fatigue stressing hardens the material which, however, disappears by stress relief annealing. By taking x-ray diffraction patterns of the surface as well as of the portions beneath the surface of the specimens, it was revealed that the distorsion and fragmentation of the grain in fatigued specimens decrease as the distance of the irradiated grain from the surface increases and it was concluded that, as the thickness of the severely damaged layer reaches some threshold value (of one or two grains thickness), fatigue cracks develop there which, in most cases, lead the plain specimens to break down eventually.
社団法人日本機械学会の論文
1963-10-25