@article{oai:kanazawa-u.repo.nii.ac.jp:00008346, author = {矢島, 善次郎 and 広瀬, 幸雄 and 田中, 啓介 and 小河, 弘}, issue = {363}, journal = {材料=Journal of the Society of Materials Science, Japan}, month = {Dec}, note = {The fracture toughness tests of ductile cast iron (JIS FCD 60) were conducted at ambient and low temperatures by using compact tension specimens and three-point bending specimens with fatigue pre-cracks. The distribution of the half-value breadth of X-ray diffraction profiles beneath the fracture surface was determined. Based on those results and electron fractographic observation, the mechanism of fracture in ductile cast iron was discussed as a function of test temperature. The main results are summarized as follows : (1) The size of the plastic zone ω_y determined from the half-value breadth distribution is related to the fracture toughness K_i through ω_y=0.13(K_i/σ_Y)^2 where σ_Y is the yield stress. (2) The fracture toughness decreased with lowering temperature and the fracture mode of the matrix changed from dimples to cleavage. The unique relation was established between the fracture surface strain and K^2_i/σ_Y., 金沢大学大学院自然科学研究科, 金沢大学大学院自然科学研究科}, pages = {1345--1350}, title = {球状黒鉛鋳鉄の低温における破壊じん性のX線フラクトグラフィ的研究}, volume = {32}, year = {1983} }