锌漆薄膜/2Cr13钢基体系统薄膜裂纹试验与模拟  

Experimental study and simulation of film cracks on Zinc film/2Cr13 steel substrate

作　　者：张华[1] 王悦 杨健[1] 李启亮 ZHANG Hua;WANG Yue;YANG Jian;LI Qiliang(School of Civil and Transportation,Hohai University,Nanjing 210000,China)

机构地区：[1]河海大学土木与交通学院,南京210000

出　　处：《复合材料学报》2019年第4期938-945,共8页Acta Materiae Compositae Sinica

摘　　要：本文采用试验和数值模拟方法研究锌漆薄膜/2Cr13钢基体系统薄膜开裂和裂纹扩展情况。创新性地使用三点弯曲试验结合声发射技术监测到薄膜裂纹萌生时刻,并计算薄膜断裂韧性。采用扩展有限元法研究三点弯曲作用下薄膜裂纹扩展过程,发现模拟得到的荷载-位移曲线与试验曲线相吻合。模拟结果表明,薄膜裂纹尖端区域存在应力峰值,当该值达到损伤判据临界应力时,裂纹发生扩展。同时,对多种因素影响下薄膜周期裂纹无量纲能量释放率进行分析,发现薄膜厚度一定时,薄膜相对于基体刚度越大,半无限基体上薄膜裂纹前缘达到稳定状态时对应的基体厚度与裂纹间距越大。In this paper,the film cracking and propagation of Zinc film/2Cr13 steel substrate system were investigated from experiments and numerical simulations.The crack initiation threshold of Zinc film was detected by the three-point bending test with the acoustic emission technique and the film fracture toughness was calculated.The extended finite element method was adopted to analyze the crack propagation of Zinc film under the three-point bending,and the load-displacement curve simulated by extended finite element method(XFEM)is consistent with the experimental result.Simulation results show that the stress peak occurs in the area of the film crack tip,and the crack propagates when the stress reaches the critical stress of the damage criterion.Meanwhile,the dimensionless energy release rate of period film cracks under various factors was analyzed.It is found that for the same film thickness,when the film crack on a semi-infinite substrate reaches a stable state,the greater the film stiffness is,the greater the substrate thickness and the crack thickness are.

关 键 词：锌漆薄膜 2Cr13钢基体 声发射 薄膜断裂韧性 裂纹尖端应力场 扩展有限元法 无量纲能量释放率 

分 类 号：TU561[建筑科学—建筑技术科学]