摘要
泡沫金属在实际工程中往往承受复杂多轴加载工况,且受到突发性爆破等极端动荷载的影响,处于多轴动态复杂应力状态。目前,受实验条件限制,泡沫金属难以实现任意比例的真三轴动态实验。本文采用数值模拟方法,采用霍普金森杆和解析刚体,分别施加冲击荷载和侧限荷载,实现了泡沫金属真三轴动态实验,且实验过程中满足应力均匀性条件,同时,探究了不同侧限条件和侧向预压力比例对泡沫金属多轴冲击性能的影响。结果表明:沿着冲击方向施加2 MPa的预压力对应力幅值为200 MPa的梯形应力波双向冲击的泡沫金属冲击性能无明显影响;侧限约束的增强能提高泡沫金属抗冲击承载能力;当冲击变形模式主导胞孔结构变形时,泡沫金属三向预压力比例对其抗冲击能力无明显影响。
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,u sing Hopkinson bar and analytical rigid body to apply impact load and lateral restraints respectively.In addition,the stress uniformity condition was satisfied during the experiment.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 loading 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.
作者
张晓阳
赵飘
刘泽宇
陈国豪
王治樵
ZHANG Xiaoyang;ZHAO Piao;LIU Zeyu;CHEN Guohao;WANG Zhiqiao(School of Mathematics and Physics,University of South China,Hengyang,Hunan 421001,China;School of Civil Engineering,University of South China,Hengyang,Hunan 421001,China)
出处
《南华大学学报（自然科学版）》
2024年第1期46-52,共7页
Journal of University of South China：Science and Technology
基金
国家自然科学基金项目(11902140)。
关键词
泡沫金属
动态冲击
侧限加载
三轴应力比
metallic foams
dynamic impact
lateral restraint
stress triaxiality
