Ti(C,N)基金属陶瓷显微组织及相界面较复杂,需要一种简便、精确的定量金相方法来辅助研究.采用功能强大的Gatan Digital Micrograph软件对不同纳米添加量Ti(C,N)基金属陶瓷显微组织进行背底消除、滤波、二值化及图像形态学处理,分析可...Ti(C,N)基金属陶瓷显微组织及相界面较复杂,需要一种简便、精确的定量金相方法来辅助研究.采用功能强大的Gatan Digital Micrograph软件对不同纳米添加量Ti(C,N)基金属陶瓷显微组织进行背底消除、滤波、二值化及图像形态学处理,分析可得到该金相图中的一些金相特征参数.对不同纳米添加量Ti(C,N)基金属陶瓷中硬质相进行了综合分析,结果表明,利用Gatan Digi-tal Micrograph软件实现Ti(C,N)基金属陶瓷显微组织的分析测量是完全可行的,能有效地提高工作效率及得到直观、准确的结果,也可定量地得到随纳米粉添加量的不断增加,硬质相颗粒的总体积不断减少,平均粒径也在不断减小.展开更多
Morphology of hydraulic fracture surface has significant effects on oil and gas flow,proppant migration and fracture closure,which plays an important role in oil and gas fracturing stimulation.In this paper,we analyze...Morphology of hydraulic fracture surface has significant effects on oil and gas flow,proppant migration and fracture closure,which plays an important role in oil and gas fracturing stimulation.In this paper,we analyzed the fracture surface characteristics induced by supercritical carbon dioxide(SC-CO_(2))and water in open-hole and perforation completion conditions under triaxial stresses.A simple calculation method was proposed to quantitatively analyze the fracture surface area and roughness in macro-level based on three-dimensional(3D)scanning data.In micro-level,scanning electron micrograph(SEM)was used to analyze the features of fracture surface.The results showed that the surface area of the induced fracture increases with perforation angle for both SC-CO_(2)and water fracturing,and the surface area of SC-CO_(2)-induced fracture is 6.49%e58.57%larger than that of water-induced fracture.The fractal dimension and surface roughness of water-induced fractures increase with the increase in perforation angle,while those of SC-CO_(2)-induced fractures decrease with the increasing perforation angle.A considerable number of microcracks and particle peeling pits can be observed on SC-CO_(2)-induced fracture surface while there are more flat particle surfaces in water-induced fracture surface through SEM images,indicating that fractures tend to propagate along the boundary of the particle for SC-CO_(2)fracturing while water-induced fractures prefer to cut through particles.These findings are of great significance for analyzing fracture mechanism and evaluating fracturing stimulation performance.展开更多
This paper deals with detailed corrosion analysis of explanted devices. The study of total 6 different types of orthopedic metallic implant was carried out after collecting the clinical report from the doctors, who pe...This paper deals with detailed corrosion analysis of explanted devices. The study of total 6 different types of orthopedic metallic implant was carried out after collecting the clinical report from the doctors, who performed these implantations. The clinical report covered the purpose of implantation, body part where implantation was done, and physiological reasons of removal of implant. The metallurgical investigation to study corrosion and any other mechanical damage to the implant surface during their service period was done using the Scanning Electron Micrography. SEM presented in this paper reveals the presence of in-vitro corrosion and mechanical damage as well, which are corroborating well with clinical reports.展开更多
文摘Ti(C,N)基金属陶瓷显微组织及相界面较复杂,需要一种简便、精确的定量金相方法来辅助研究.采用功能强大的Gatan Digital Micrograph软件对不同纳米添加量Ti(C,N)基金属陶瓷显微组织进行背底消除、滤波、二值化及图像形态学处理,分析可得到该金相图中的一些金相特征参数.对不同纳米添加量Ti(C,N)基金属陶瓷中硬质相进行了综合分析,结果表明,利用Gatan Digi-tal Micrograph软件实现Ti(C,N)基金属陶瓷显微组织的分析测量是完全可行的,能有效地提高工作效率及得到直观、准确的结果,也可定量地得到随纳米粉添加量的不断增加,硬质相颗粒的总体积不断减少,平均粒径也在不断减小.
基金National Natural Science Foundation of China(Grant No.51804318)the China Postdoctoral Science Foundation Founded Project(Grant No.2019M650963)National Key Basic Research and Development Program of China(Grant No.2014CB239203).
文摘Morphology of hydraulic fracture surface has significant effects on oil and gas flow,proppant migration and fracture closure,which plays an important role in oil and gas fracturing stimulation.In this paper,we analyzed the fracture surface characteristics induced by supercritical carbon dioxide(SC-CO_(2))and water in open-hole and perforation completion conditions under triaxial stresses.A simple calculation method was proposed to quantitatively analyze the fracture surface area and roughness in macro-level based on three-dimensional(3D)scanning data.In micro-level,scanning electron micrograph(SEM)was used to analyze the features of fracture surface.The results showed that the surface area of the induced fracture increases with perforation angle for both SC-CO_(2)and water fracturing,and the surface area of SC-CO_(2)-induced fracture is 6.49%e58.57%larger than that of water-induced fracture.The fractal dimension and surface roughness of water-induced fractures increase with the increase in perforation angle,while those of SC-CO_(2)-induced fractures decrease with the increasing perforation angle.A considerable number of microcracks and particle peeling pits can be observed on SC-CO_(2)-induced fracture surface while there are more flat particle surfaces in water-induced fracture surface through SEM images,indicating that fractures tend to propagate along the boundary of the particle for SC-CO_(2)fracturing while water-induced fractures prefer to cut through particles.These findings are of great significance for analyzing fracture mechanism and evaluating fracturing stimulation performance.
文摘This paper deals with detailed corrosion analysis of explanted devices. The study of total 6 different types of orthopedic metallic implant was carried out after collecting the clinical report from the doctors, who performed these implantations. The clinical report covered the purpose of implantation, body part where implantation was done, and physiological reasons of removal of implant. The metallurgical investigation to study corrosion and any other mechanical damage to the implant surface during their service period was done using the Scanning Electron Micrography. SEM presented in this paper reveals the presence of in-vitro corrosion and mechanical damage as well, which are corroborating well with clinical reports.
