Damage and fracture behavior of self - reinforced polyethylene ( pe ) composite under monotonic tensile loading were investigated by acoustic emission ( ae ) technique 摘要用声发射( ae )技术研究了聚乙烯自增强复合材料的拉伸损伤与断裂行为。
In conclusion , the research of this thesis indicate that the behavior of crack with a arc - tip is the same as that of a spiculate crack , but its load of fracture initiation is higher than the latter 总之，本文的研究结果表明，裂尖宽度为0 . 12mm的非尖锐裂纹的断裂行为与尖锐裂纹基本相同，但起裂载荷较高。
It is concluded that the coulomb - type crack model is suitable for simulation of the interfacial fracture under mixed - mode fracture loads , however further work is still needed for improvement of its dilatancy properties 通过对数值结果的分析比较得出结论：库仑型裂纹模型比较适合模拟复杂载荷下的界面断裂行为，但是其扩容特性仍有待改善。
In this paper , the problems relevant to the hydrogen embrittlement of titanium alloy has been summarized comprehensively . and based on those vies , the influence of hydrogen on the microstructure and mechanical properties of the titanium alloy ti - 2al - 2 . 5zr was studied , the solubility of hydrogen in the alloy has been measured , hydrogen induced delayed fracture behavior in it has been investigated , and finally the hydrogen induced delayed fracture behavior model was proposed 本文详细评述了国内外对钛合金的氢脆及相关问题的研究进展，并在此基础上，研究了氢对ti - 2al - 2 . 5zr合金的组织结构和力学性能的影响，测试了氢在该合金中的溶解度，并对其氢致延迟断裂行为进行了分析研究，提出了氢致延迟断裂的断裂机理。
The constitutive equations were gained by regression analysis and some material constants were derived from that with the aid of om , x - ray , sem and tem , the deformation structure of the mid - strength weldable 1420aluminum - lithium alloy on different hot deformation conditions was studied and the soften mechanism was discussed . at the same time , the fracture behavior has been studied as an important part . the fracture mechanism of 1420 aluminum - lithium alloy was confirmed 结合金相显微镜、 x -射线衍射、扫描电镜、透射电镜等现代化的试验手段，研究了中强可焊1420铝锂合金热变形不同变形条件下的组织变化及软化机制，分析了不同变形条件对合金材料组织变化的影响，确定了合金材料的软化行为机理；同时，结合合金材料的热变形高温拉伸试验，重点研究了材料的断裂行为，分析了合金材料的断裂现象，探讨了合金材料的断裂机理。
The effects of the fabrication and heat - treatment methods on the microstructures and properties of the nb - si system intermetallics have been studied and the optimized nb - si intermetallic system as well as the optimized fabrication and processing procedures have been selected . the presence of alloying elements as well as the morphology and microstructure of the compound phases with these elements has been investigated . the effects of the alloying elements on the high - temperature oxidation behavior of the nb - si system intermetallics have also been studied 本文研究了不同的制备工艺和热处理制度对nb - si系金属间化合物显微组织和性能的影响，优选了合适的材料体系、制备工艺和热处理制度，分析了微合金化元素及其形成相的组织、结构、形态、存在形式等及其对材料高温抗氧化行为的影响，提出了材料高温抗氧化行为和室温断裂行为的微观机制，为研制nb - si系金属间化合物基高温结构材料奠定了一定的基础。
Aiming at the simulation of quasi - brittle fracture of concrete - like materials , the qualitative comparison of the selected models was focused on the follow aspects , i . e . the simulation of the fracture behaviors of crack mode and crack mode by use of the selected models and the simulation of dilatancy properties of the selected models under mixed - mode fracture loading conditions 在对选择的典型黏性界面裂纹进行定性分析比较时着重考虑以下两点：采用选择的模型对型裂纹和型裂纹的断裂行为进行数值计算；对混合型断裂载荷作用下模型的扩容行为特性进行数值分析。
