摘要
绝大多数金属均存在复杂的应变率效应,屈服强度和流变应力在不同应变速率下的值不同,不同应变速率范围内应力变化趋势也会不同,表现为应变率强化效应和应变率弱化效应。应变速率影响着金属材料的宏观力学性能以及内部微观组织结构,不同变形速度下的金属材料塑性变形行为存在明显差异。在板材高速拉深等高速冷成形过程中,材料局部应变速率的提升将导致该区域内塑性变形功转化为热量造成瞬时温升,局部的高温高压使材料的拉深成形性能和表面质量受到不同程度的影响。在金属板材高速成形领域,建立考虑应变率效应以及绝热温升效应影响的动态本构模型是准确获取材料力学行为响应、实现形性一体化高精密成形的重要前提。综述金属应变率效应以及应变速率对金属塑性变形行为的影响,并对金属动态力学行为和动态本构模型研究进展进行了总结,着重对唯象本构、物理本构、人工神经网络本构这三类模型的研究工作,以及流变应力的应变率效应进行了论述和分析,最后就金属应变率效应研究和构建金属高速成形动态本构关系研究工作中的不足进行了总结讨论,为开展金属高速成形动态本构相关的研究工作给出了一定的建议和展望。
Most metals have complex strain rate effects.The yield strength and flow stress have different values at different strain rates,and the stress variation trend will be different at different strain rates,which is manifested as the strain rate strengthening effect and strain rate weakening effect.The strain rate affects the macroscopic mechanical properties and internal microstructure of metal materials,and there are obvious differences in the plastic deformation behavior of metal materials under different deformation rates.In the process of high-speed cold forming such as high-speed drawing of the plate,the increase of the local strain rate of the material will lead to an instantaneous temperature rise,and the local high temperature and high pressure will affect the drawing forming performance and surface quality of the material to varying degrees.In the field of high-speed sheet metal forming,establishing a dynamic constitutive model that considers the strain rate effect and adiabatic temperature rise effect is an important prerequisite for accurately obtaining the mechanical behavior response of materials and realizing high-precision forming with integrated formability.Firstly,the metal strain rate effect,as well as the effect of strain rate on the plastic deformation behavior of metals are introduced,furthermore,the research progress of metal dynamic mechanical behavior and dynamic constitutive model is summarized,and the strain rate effect on flow stress,as well as the research work of phenomenological constitutive,physical constitutive and artificial neural network constitutive models is also discussed and analyzed,finally,the deficiencies in the research of metal strain rate effect and the construction of dynamic constitutive relationship of metal high-speed forming are summarized and discussed.Some suggestions and prospects are given for the research work related to the dynamic constitutive of metal high-speed forming.
作者
徐腾
邓春阳
冉家琪
龚峰
唐恒
XU Teng;DENG Chunyang;RAN Jiaqi;GONG Feng;TANG Heng(College of Mechatronics and Control Engineering,Shenzhen University,Shenzhen 518060;Shenzhen Key Laboratory of High Performance Nontraditional Manufacturing,Shenzhen University,Shenzhen 518060)
出处
《机械工程学报》
EI
CAS
CSCD
北大核心
2024年第2期81-98,共18页
Journal of Mechanical Engineering
基金
国家自然科学基金(52005341)
中国台北科技大学与深圳大学学术合作专题研究计划经费补助(2023010)资助项目。
关键词
应变率效应
高速成形
绝热温升
动态力学行为
动态本构模型
strain rate effect
high speed forming
adiabatic temperature rise
dynamic mechanical behavior
dynamic constitutive model
