摘要
为了研究爆炸焊接界面的剪切损伤行为,本文对铝-铝复合材料开展剪切试验,并基于分形理论对试件剪切断口界面进行表征,尝试建立界面剪切强度与断口轮廓分维值及其多重分形谱关系。结果表明,焊接界面剪切强度随加载速率升高而降低,异于通常金属剪切行为;但从断口形貌及其轮廓分形维可认识界面剪切强度变化原因。此外,多重分形谱起点与终点间的高度差和跨度差值反映了界面的峰、谷落差及分布特征,是界面形貌特征的立体反映,并在数值上也与剪切强度正相关。
In order to understand the shear damage behavior of explosive welding interface,shear experiment of Al-Al composite was carried out,and fracture interface was characterized based on fractal theory.The purpose of above study is to attempt to establish the relation among interface shear strength,fracture profile fractal dimension value and its multifractal spectrum.Results show that welded interface shear strength decreases with the increase of loading rate,which is different from ordinary shear behavior of metal material;but based on SEM（scanning electron microscope）image,the reason of interfacial shear strength change can be recognized from fracture morphology and contour fractal dimension.Besides,the difference of the height（vertical）and span（horizontal）between starting point and endpoint of multifractal spectrum reflects peak and trough value of interface and distribution features.It is the stereoscopic vision of interface morphology,and also has positive numerical relation with shear strength.
出处
《实验力学》
CSCD
北大核心
2015年第2期165-172,共8页
Journal of Experimental Mechanics
基金
国家自然科学基金(11202093)
关键词
爆炸焊接
剪切强度
分形
多重分形谱
explosive welding
shear strength
fractal
multifractal spectrum
