摘要
采用电液伺服高速拉伸试验机获得双相高强钢DP780D＋Z在不同应变速率下的力学性能曲线,结合拉伸断口组织和形貌变化,分析不同应变速率下材料的力学性能及微观组织变化。分析结果可知：低应变速率下,材料的抗拉强度、屈服强度等变化不明显,随着应变速率的增加,力学性能提升明显;当应变速率达到10 s^-1后,材料的断后伸长率均出现较大幅度的变化,材料的塑性具有明显的提升;随着应变速率的增加,双相钢内的基体之间的运动阻力增大,表现出材料非均匀塑性变形能力增强;当应变速率比较低时,材料断口表现出非常明显的拉长韧窝特征,随着应变速率的增加,等轴韧窝特性越来越明显,双相钢表现出明显的韧性断裂特征。
The mechanical properties of the double-phase high strength steel DP780 D ＋ Z at different strain rates were obtained by the electro-hydraulic servo high-speed tensile testing machine,and the mechanical properties and microstructure of material were analyzed by combining the tensile fracture structure and morphological change. The results show that the tensile strength and yield strength of the material do not change obviously at low strain rate,and with the increase of the strain rate,the mechanical properties are improved obviously.When the strain rate reaches 10 s^-1,the elongation after fracture changes greatly,and the plasticity of the material increases quickly.Furthermore,with the increase of strain rate,the movement resistance between the matrices in the dual-phase steel increases which shows strong non-uniform plastic deformation ability. When the strain rate is relatively low,the material fracture shows a very obvious characteristic of elongated dimple,and with the increase of strain rate,the equiaxial dimple feature is more obviously and the dual-phase steel has the ductile fracture obviously.
作者
李春光
张伟
刘立现
陈庆
Li Chunguang;Zhang Wei;Liu Lixian;Chen Qing(School of Materials and Metallurgy, Northeastern University, Shenyang 110819, China;Application Technology Department, Shougang Research Institute of Technology, Beijing 100043, China)
出处
《锻压技术》
CAS
CSCD
北大核心
2018年第6期166-171,共6页
Forging & Stamping Technology
关键词
应变速率
双相高强钢
动态力学行为
微观机理
韧性断裂
strain rate
high-strength steel with dual-phase
dynamic mechanical behavior
micro-mechanism
ductile fracture
