ntergranular slow crack growth in zirconia polycrystal is described with a cohesive zone model that simulate mechanically the reaction-rupture mechanism underlying stress and environ- mentally assisted failure. A 2D p...ntergranular slow crack growth in zirconia polycrystal is described with a cohesive zone model that simulate mechanically the reaction-rupture mechanism underlying stress and environ- mentally assisted failure. A 2D polycrystal is considered with cohesive surfaces inserted along the grain boundaries. The anisotropic elastic modulus and grain-to-grain misorientation are accounted for together with an initial stress state related to the processing. A minimum load threshold is shown to originate from the onset of the reaction-rupture mechanism to proceed where a minimum traction is reached locally and from the magnitude of the initial compression stresses. This work aims at providing reliable predictions in long lasting applications of ceramics.展开更多
聚乙烯(PE)管材在施工和使用过程中会产生裂纹并缓慢扩展,评价耐慢速裂纹增长性能包括原料测试和管材测试两部分。介绍了国际标准和国家标准中关于耐慢速裂纹增大试验的要求、原理和应用,并列举了通过切口试验加速老化评价和预测 PE 原...聚乙烯(PE)管材在施工和使用过程中会产生裂纹并缓慢扩展,评价耐慢速裂纹增长性能包括原料测试和管材测试两部分。介绍了国际标准和国家标准中关于耐慢速裂纹增大试验的要求、原理和应用,并列举了通过切口试验加速老化评价和预测 PE 原料长期性能和使用寿命的几种方法。展开更多
Double edge notched tensile (DENT) tests were carried out to investigate the slow crack growth (SCG) behavior of PESO welded joints. Efforts were made to acquire creep fracture parameters which can characterize cr...Double edge notched tensile (DENT) tests were carried out to investigate the slow crack growth (SCG) behavior of PESO welded joints. Efforts were made to acquire creep fracture parameters which can characterize creep resistance. Results show that creep compliance indicates an ascending trend with the increase of applied stress. A global creep load parameter is obtained. It has a linear relationship with fkacture time in logarithmic coordinate system and helps to predict the fracture time at any applied load.展开更多
文摘ntergranular slow crack growth in zirconia polycrystal is described with a cohesive zone model that simulate mechanically the reaction-rupture mechanism underlying stress and environ- mentally assisted failure. A 2D polycrystal is considered with cohesive surfaces inserted along the grain boundaries. The anisotropic elastic modulus and grain-to-grain misorientation are accounted for together with an initial stress state related to the processing. A minimum load threshold is shown to originate from the onset of the reaction-rupture mechanism to proceed where a minimum traction is reached locally and from the magnitude of the initial compression stresses. This work aims at providing reliable predictions in long lasting applications of ceramics.
文摘Double edge notched tensile (DENT) tests were carried out to investigate the slow crack growth (SCG) behavior of PESO welded joints. Efforts were made to acquire creep fracture parameters which can characterize creep resistance. Results show that creep compliance indicates an ascending trend with the increase of applied stress. A global creep load parameter is obtained. It has a linear relationship with fkacture time in logarithmic coordinate system and helps to predict the fracture time at any applied load.