Abstract
Experimental investigations on dynamic in-plane compressive behavior of a plain weave composite were performed using the split Hopkinson pressure bar.A quantitative criterion for calculating the constant strain rate of composites was established.Then the upper limit of strain rate,restricted by stress equi-librium and constant loading rate,was rationally estimated and confirmed by tests.Within the achiev-able range of 0.001/s-895/s,it was found that the strength increased first and subsequently decreased as the strain rate increased.This feature was also reflected by the turning point(579/s)of the bilinear model for strength prediction.The transition in failure mechanism,from local opening damage to completely splitting destruction,was mainly responsible for such strain rate effects.And three major failure modes were summarized under microscopic observations:fiber fracture,inter-fiber fracture,and interface delamination.Finally,by introducing a nonlinear damage variable,a simplified ZWT model was devel-oped to characterize the dynamic mechanical response.Excellent agreement was shown between the experimental and simulated results.
基金项目
National Science and Technology Major Project(2017-VII-0011-0106)
Natural Science Foundation of Heilongjiang Province(ZD2019AO01)
维普
万方数据