Spray deposited porous aluminum alloy sheets easily have surface and edge crack when they are directly rolled due to the porosity and metallurgical bond 摘要喷射沉积多孔铝合金板坯由于有孔洞且缺乏良好的冶金结合，直接轧制时易出现板坯表面裂纹及边裂。
Experimental results show that the morphological wavelet transform presented here is more effective than other techniques for the detection of surface crack defects of a medium heavy plate 实验证明形态小波用来检测中厚板表面裂纹缺陷比用其他方法更有效。
Through the improvement to the press craft for the heavy wall - head , avoids the production of its surface crack , guarantees the products ' quality , it offered the reference for the work in the future 摘要通过对厚壁封头压制工艺的改进，避免了其表面裂纹的产生，保证了产品质量，为今后的厚壁封头压制工作提供了参考依据。
The stress intensity factor for surface crack in " t " type of plate welded joint is computed , and the computation shows that agreement is achieved between the calculation and practical measured result 计算表明，用线弹簧单元和有限元相结合的方法，计算表面裂纹的应力强度因子，可以大量减少计算工作量，且具有良好的计算精度。
It is difficult to extract crack defects from a defect image by traditional detection techniques , for the image of surface crack defects on a medium plate is influenced greatly by background noise and oxidized scale 摘要中厚板表面裂纹缺陷在图像中容易受背景噪声和氧化铁皮的影响，传统的图像处理方法很难将裂纹缺陷从图像中检测出来。
By means of inspection analysis , the reasons of surface cracking forming were found out , which existed on the three towers in a wax catalysis unit , and the countermeasure of controlling surface cracking forming were proposed 摘要通过检验分析，找出了某蜡油催化装置吸收稳定三塔连续多年出现表面裂纹的原因，并提出了有效的防护措施。
Based on the line spring model of rice and levy , this paper sets up eight nodes line spring element and its stiffness matrixes and works out a program consist of prism element , hexahedron element and line spring element 编制了五面体单元、六面体单元和八节点线弹簧单元相结合的计算程序，计算了t型板接头表面裂纹的应力强度因子，计算值与光弹性试验结果吻合较好。
An losipescu - type of fixture , which had been previously used for the static shear strength tests of unidirectional laminates or metal materials , was proved useful for the shear static and fatigue tests of multidirectional laminates ( 6 )进行mdyb - 3座舱盖有机玻璃撞击损伤剩余强度和疲劳裂纹扩展试验，发现撞击损伤引致的疲劳裂纹的扩展规律与理想的表面裂纹明显不同。
Studying the rule of geometric shape of surface crack during propagation by means of fracture mechanics theory , a predicting method of fatigue crack propagation life and it ' s numerical calculation theory are presented 本文应用断裂力学理论，对焊接钢结构表面裂纹扩展过程中裂纹几何形状的变化规律进行了探讨，提出了疲劳裂纹扩展寿命的预测方法，给出了相应的数值计算理论。
The study gives a qualitative and quantitative dynamic fracture analysis , and a three - dimensional finite element program is developed to compute the dynamic stress intensity factor for a semi elliptic surface crack in an elastic solid of finite size under impact loading 在定量分析中，编写了该裂纹结构受冲击载荷作用下的全尺寸三维动态有限元程序，并进行了大规模的数值计算，确定了表面裂纹动态应力强度因子，论证了该事故发生的原因。
