Resistance welding of carbon fibre reinforced polyetheretherketone composites using metal mesh and PEI film

Weldability of polyetheretherketone( PEEK) with polyetherimide( PEI) is tested. And carbon fiber reinforced PEEK laminates are resistance welded using stainless steel mesh heating element. The effects of the welding time and welding pressure on the lap shear strength of joints are investigated. Results show that PEEK can heal with PEI well in welding condition and the lap shear strength of PEEK/CF(carbon fibre) joint increases linearly with welding time, but reaches a maximum value when welding pressure ranging from 0.3 MPa to 0.5 MPa with constant welding time. The fracture characteristics of surface are analyzed by SEM techniques, and four types of fracture modes of lap shear joints are suggested.     

浅谈建筑抗震概念设计

"建筑抗震概念设计"是根据地震灾害和工程经验等,所形成的基本设计原则和设计思想,是进行建筑和结构总体布置,并确定细部构造的过程.它是构造建筑物良好结构性能的决定性因素.对于设计工作者和决策者审定建筑、结构方案有着重要的意义.     

框架—双核心筒结构体系的实例分析

框架—双核心筒结构体系,经过计算分析,该结构体系可取得较好的抗侧刚度,能满足现行规范的要求,这种结构体系具有减轻自重、提高刚度、扩大建筑空间的优点,是高层建筑结构比较经济、合理、可行的一种结构体系。     

金属基复合材料界面强度测试方法的研究

通过对拉拔法和顶出法的试样制备、测试方法和两种方法的对比等方面的研究,得知顶出法更适合于金属基复合材料界面强度的测试.     

石家庄社保局商住楼结构设计特点

文章介绍了石家庄社保局商住楼结构设计特点,框支剪力墙结构,设置转换层,采用梁式转换,能够有效地解决大空间使用要求。     

张志斌大师菜品欣赏

~~张志斌大师菜品欣赏@赵新英     

Effects of spinneret structure on poly-ether-ether-ketone fibers by screw extrusion

According to the characters of poly-ether-ether-ketone (PEEK) plastic, the spinnerets with three kinds of different structure were designed. The effects of spinneret structure on the melt spinning conditions, melt flow instability of the screw extrusion, and the performance of PEEK fibers were studied. The results show that the appropriate screw extrusion temperature is 370-385℃. The PEEK fibers extruded using the spinnerets with L/D=6,8 holes and 0.5 mm in diameter have better performances. The performances of PEEK fibers are related to the diameter of the spinneret hole. Increasing the L/D value of the spinnerets can not always improve the surface quality and the performances of PEEK fibers. The extrusion pressure is about 50% of that of the spinneret with 12 holes and 0.3mm in diameter.     

故障树分析法在电子式过载保护继电器中的应用

电子式过载保护继电器主要用于实现电动机的过载保护,其可靠性的高低直接影响电动机的可靠运行。在简要介绍了智能化电子式过载保护继电器硬件结构的基础上,采用故障树分析法(FTA法)对其进行了可靠性的定性分析。利用建立的故障树,求出了系统的最小割集,从而找出了系统的关键环节,并提出了提高电子式过载保护继电器可靠性的一些措施。     

故障树分析法在电子式过载保护继电器中的应用

电子式过载保护继电器主要用于实现电动机的过载保护,其可靠性的高低直接影响电动机的可靠运行.在简要介绍了智能化电子式过载保护继电器硬件结构的基础上,采用故障树分析法(FTA法)对其进行了可靠性的定性分析.利用建立的故障树,求出了系统的最小割集,从而找出了系统的关键环节,并提出了提高电子式过载保护继电器可靠性的一些措施.     

多组元复合功能陶瓷粉体制备技术研究进展

综述了多组元复合功能陶瓷粉体制备技术的研究进展，较详细地介绍了新出现的凝胶固相反应合成法的工艺及其特点。