摘要
试验表明,大多数工程材料在冲击载荷作用之下的变形一般都同时包含有可恢复的瞬态性弹性变形和不可恢复的粘滞性塑性变形,即其本构关系可以用弹粘塑性模型来描述。本文从内变量理论出发,探讨了时率相关材料的弹粘塑性本构关系的一般特性,建立了增量型的弹粘塑性本构关系的一般理论框架和普适的表达式,并且对两种最常用的本构模型--Bodnet-Partom模型和Johnson-Cook模型给出了在一维应变条件下的具体形式。通过计算和讨论一维应变粘塑性靶板中冲击波的衰减机制和应力波的演化规律,特别是考察各种粘塑性本构模型中的材料参数对冲击波的衰减和应力波的演化的影响,得出了一些可以直接应用或具有一定借鉴价值的结果,为研究应力波的其他衰减机制以及在人防工程中智能防护层设计时新材料的选取奠定了基础。
Based on the experiment, the deformation of most engineering materials under impact loading is generally consist of the transient elastic deformation which is restorable and the viscous plastic deformation which is not restorable, thus the elastic viscoplastic models can be used to describe the constitutive relations of these materials. The elastic viscoplastic constitutive characters for rate dependent materials were investigated based on the internal variables theory. General theory frame and universal formula of incremental strain constitutive relations for these materials were proposed. And the concrete forms for two kinds of most useful constitutive models-Bodner Partom model and Johnson Cook model under one dimension strain condition were also presented. And thereby the numerical simulations were carried out for the attenuation mechanism of shock waves and evolution rules of stress waves in an one dimension strain viscoplastic target, especially for the effects of the parameters in these models. These results that can be applied directly or used for reference are considered as the basic of researching for other attenuation mechanisms of stress waves and of selecting new materials while designing the intelligent safeguard.
出处
《力学季刊》
CSCD
北大核心
2004年第3期410-416,共7页
Chinese Quarterly of Mechanics
关键词
粘塑性本构关系
应力波
演化规律
elastic viscoplastic constitutive relations
stress waves
evolution rules
