The carbon fiber reinforced composite is a new type of composite material with an excellent property in strength and elastic modulus,and has found extensive applications in aerospace,energy,automotive industry and so ...The carbon fiber reinforced composite is a new type of composite material with an excellent property in strength and elastic modulus,and has found extensive applications in aerospace,energy,automotive industry and so on.However,this composite has a strict requirement on processing techniques,for example,brittle damage or delamination often exists in conventional processing techniques.Abrasive water jet machining technology is a new type of green machining technique with distinct advantages such as high-energy and thermal distortion free.The use of abrasive water jet technique to process carbon fiber composite materials has become a popular trend since it can significantly improve the processing accuracy and surface quality of carbon fiber composite materials.However,there are too many parameters that affect the quality of an abrasive water jet machining.At present,few studies are carried out on the parameter optimization of such a machining process,which leads to the unstable quality of surface processing.In this paper,orthogonal design of experiment and regression analysis were employed to establish the empirical model between cutting surface roughness and machining process parameters.Then a verified model was used to optimize the machining process parameters for abrasive water jet cutting carbon fiber reinforced composites.展开更多
在工程建设中,废弃泥浆含水率极高,且对环境的影响极大,解决其脱水问题成为当前面临的主要难题。针对高含水率泥浆泥水分离问题,选择3种絮凝剂:氯化钙(CaCl_(2))、阴离子型聚丙烯酰胺(APAM)和聚合氯化铝(PAC),设计3因素4水平正交试验,...在工程建设中,废弃泥浆含水率极高,且对环境的影响极大,解决其脱水问题成为当前面临的主要难题。针对高含水率泥浆泥水分离问题,选择3种絮凝剂:氯化钙(CaCl_(2))、阴离子型聚丙烯酰胺(APAM)和聚合氯化铝(PAC),设计3因素4水平正交试验,采用综合平衡法,选取48 h脱水量和上清液pH值等指标,进行极差分析和方差分析,着重找出最佳复合絮凝剂组合。通过正交试验结果和SEM微观分析等对絮凝机理进行讨论。结果表明,将脱水量随时间变化曲线划分为高、中、低脱水区和快速脱水、慢速脱水阶段,则泥浆脱水速率整体呈减小趋势,其中高脱水区组在12 h时也具有较高的脱水量,即满足快速脱水的要求;3种絮凝剂存在一定的协同作用效果。通过正交试验的极差分析和方差分析发现,复合絮凝剂的最优组合为每100 g泥浆掺量为0.25 g CaCl_(2)+0.12 g APAM+0.17 g PAC;根据机理分析,可将复合絮凝剂絮凝过程分为5个阶段:电中和阶段、架桥阶段、吸附成团阶段、网络沉降阶段和固化增强阶段。展开更多
基金National High-Tech R&D Program of China(863 Program)(2015AA043401)。
文摘The carbon fiber reinforced composite is a new type of composite material with an excellent property in strength and elastic modulus,and has found extensive applications in aerospace,energy,automotive industry and so on.However,this composite has a strict requirement on processing techniques,for example,brittle damage or delamination often exists in conventional processing techniques.Abrasive water jet machining technology is a new type of green machining technique with distinct advantages such as high-energy and thermal distortion free.The use of abrasive water jet technique to process carbon fiber composite materials has become a popular trend since it can significantly improve the processing accuracy and surface quality of carbon fiber composite materials.However,there are too many parameters that affect the quality of an abrasive water jet machining.At present,few studies are carried out on the parameter optimization of such a machining process,which leads to the unstable quality of surface processing.In this paper,orthogonal design of experiment and regression analysis were employed to establish the empirical model between cutting surface roughness and machining process parameters.Then a verified model was used to optimize the machining process parameters for abrasive water jet cutting carbon fiber reinforced composites.
文摘在工程建设中,废弃泥浆含水率极高,且对环境的影响极大,解决其脱水问题成为当前面临的主要难题。针对高含水率泥浆泥水分离问题,选择3种絮凝剂:氯化钙(CaCl_(2))、阴离子型聚丙烯酰胺(APAM)和聚合氯化铝(PAC),设计3因素4水平正交试验,采用综合平衡法,选取48 h脱水量和上清液pH值等指标,进行极差分析和方差分析,着重找出最佳复合絮凝剂组合。通过正交试验结果和SEM微观分析等对絮凝机理进行讨论。结果表明,将脱水量随时间变化曲线划分为高、中、低脱水区和快速脱水、慢速脱水阶段,则泥浆脱水速率整体呈减小趋势,其中高脱水区组在12 h时也具有较高的脱水量,即满足快速脱水的要求;3种絮凝剂存在一定的协同作用效果。通过正交试验的极差分析和方差分析发现,复合絮凝剂的最优组合为每100 g泥浆掺量为0.25 g CaCl_(2)+0.12 g APAM+0.17 g PAC;根据机理分析,可将复合絮凝剂絮凝过程分为5个阶段:电中和阶段、架桥阶段、吸附成团阶段、网络沉降阶段和固化增强阶段。
