摘要
为研究AISI D2钢力学性能尺寸效应现象,在常温下采用电子万能试验机和分离式霍普金森压杆(SHPB)实验装置对3种不同剪切带宽度(分别为800,400,50μm)的帽形试样进行了准静态和动态加载实验.实验结果表明,流动应力和失效应变随着剪切带宽度的减小而增大,但产生流动应力和失效应变尺寸效应现象的剪切带宽度不同.基于应变率强化项修正的Johnson-Cook本构模型,通过实验数据拟合得到材料的本构关系.研究表明,修正的Johnson-Cook本构模型与实验结果吻合较好.
Quasi-static and dynamic shear deformation of hat shaped specimen with three different widths of shear zone (800,400,50 μm respectively)were performed by electronic universal testing machine and Split Hopkinson Pressure Bar ( SHPB ) at room temperature. The size effects of AISI D2 steel mechanical property were studied. The experimental results show that the flow stress and failure strain of material increase with the decrease of shear zone widths, however the shear zone widths which induce the size effect of flow stress and failure strain are different. Based on the Johnson-Cook constitutive model, the constitutive relation of material with different shear zone widths was fitted by the experiment results. The item of strain rate sensitivity is modi- fied, and the modified Johnson-Cook constitutive model agrees well with the experimental results.
出处
《材料科学与工艺》
EI
CAS
CSCD
北大核心
2012年第3期83-88,共6页
Materials Science and Technology
基金
国家自然科学基金资助项目(No.51105224)
国家重点基础研究发展计划资助项目(2011CB013404)
摩擦学国家重点实验室自主科研重点项目(No.SKLT10A01)