高速進展き裂に関する考察 : 微小き裂のふるまい

概要

論文の詳細を見る
When tensile stress is applied to a material, the activation energy for the generation of submicrocracks decreases and the submicrocracks are thermally generated at the tip of the crack. These submicrocracks remain stable by relaxing the elastic energy around them. The submicrocracks grow by coalescence and become unstable as the density of submicrocracks increases. The submicrocracks at this stage are considered to be disk shaped and are called microcracks in this paper. Since the stress is intensified around the microcracks, the microcracks grow by the generation of submicrocracks around them. The microcracks at this stage grow in a self-similar manner, statistically. The radius γ of the disk-shaped microcrack is found to grow in time as γ ∝ t^α, where α is a positive number. The author postulated that the initiation of the crack propagation is controlled by the growth of the microcrack generated at the tip of the crack. This postulate predicts the existence of two different velocities of the crack at initiation, when the stress intensity factor remains close to the fracture toughness. When the crack velocity is controlled by the growth of the submicrocracks at the tip of the crack, the velocity of the crack is very slow, while it becomes of the order of 10^2 m/s when it is controlled by the microcracks which grow in a self-similar manner, statistically. Such behavior of crack velocity was observed by Takahashi in 1987.
一般社団法人日本機械学会の論文
1993-04-25

高速進展き裂に関する考察 : 微小き裂のふるまい

スポンサーリンク

概要

著者

関連論文

スポンサーリンク