Study on Impact Properties of Metallic Foams Under Different Lateral Restraints and Load Proportions
Metallic foams usually sustain multiaxial and dynamic loadings in applications,which are in multiaxial dynamic complex stress state affected by extreme dynamic loads such as sudden explosion.With limitations of experiments,multiaxial dynamic experiments with variable stress triaxiality are difficult to be realized.In this paper,the true triaxial dynamic experiment of metal foam is carried out by using numerical simulation method,using Hopkinson bar and analytical rigid body to apply impact load and lateral restraints respectively.In addition,the stress uniformity condition was satisfied during the experi-ment.At the same time,the influence of different lateral confinement conditions and the ratio of lateral prestressing force on the multi-axial impact performance of metal foam was investigated.Results indicated that the pre-pressure with 2 MPa in the impact direction has no significant effect on impact properties of metallic foams under bidirectional impact load-ing with the stress amplitude of 200 MPa.The impact supportability was improved with the enhancement of lateral restraints.The stress triaxiality of pre-pressure has unremarkable influence of impact performances when cells'structures deformations are dominated by the impact deformation model.
万方数据
维普
