PMMA 中を高速進展するき裂先端付近の開口変位測定

概要

論文の詳細を見る
Pulsed holographic microscopy was applied to take an instantaneous microscopic photograph of a rapidly propagating crack in PMMA. The crack was in the opening mode and its speed was at several hundred m/s. The crack and craze opening displacement, which are both called COD, were measured as a function of distance γ from the craze tip within the region of γ up to 8 mm. The crack opening displacement was nearly proportional to √<γ>, while the craze opening displacement deviated from the curve of √<γ>. The crack tip opening displacement (CTOD) was determined from the measured COD data,and the dynamic stress intensity factor K_I(υ) was also obtained. Furthermore,the value of J-integral was calculated by assuming small scale yielding. It happens that cracks which have the same K_I(υ) value and crack speed show different COD profile in the craze layer.
1990-08-15