铁中Ⅰ型裂纹裂尖场与裂尖形变机制分析  

Analysis of the crack tip field and the deformation mechanism of mode I crack in iron

作　　者：汤笑之[1] 郭雅芳[1] 

机构地区：[1]北京交通大学土木建筑工程学院力学系,北京100044

出　　处：《计算力学学报》2011年第B04期20-24,共5页Chinese Journal of Computational Mechanics

基　　金：国家自然科学基金(10672016);中央高校基本科研业务费专项资金资助项目

摘　　要：应用有限元及连续介质力学计算了平面应变条件下体心立方铁中不同取向裂纹的裂尖应力场和弹性应变能密度分布,从宏微观相结合角度分析了裂尖场分布与裂尖微结构演化的相互关联。指出裂尖塑性变形的具体形式与裂尖滑移面上分切应力的大小密切相关,并从能量角度解释了裂尖相变产生的原因,最后结合相关分子动力学研究成果探讨了裂尖奇异性区域。In this paper, the finite element method is applied to calculate the stress field and the elastic strain energy density distribution at the crack tip. The results indicate that the microstructure evolution at ＇the crack tip is closely related with the shear stress on the slip plane near the crack tip. Moreover, the martensitic phase transformation is investigated based on the energy analysis. Finally, the truncated distance of continuum elastic field is discussed comparing with the results calculated by molecular dynamics simulations.

关 键 词：裂尖场 应变能密度 裂尖形变机制 有限元 分子动力学 

分 类 号：O346[理学—固体力学]