针对树脂传递模塑工艺(RTM)对于可用树脂的要求,研究了适用于RTM工艺的高成碳RTM酚醛树脂的相关性能,表征了高成碳RTM酚醛树脂的分子结构,分析了树脂的流变特性、树脂成碳率以及RTM工艺适用性。为了进一步制备层间性能优异的树脂基烧蚀...针对树脂传递模塑工艺(RTM)对于可用树脂的要求,研究了适用于RTM工艺的高成碳RTM酚醛树脂的相关性能,表征了高成碳RTM酚醛树脂的分子结构,分析了树脂的流变特性、树脂成碳率以及RTM工艺适用性。为了进一步制备层间性能优异的树脂基烧蚀材料,选用2.5D碳纤维编织预制体为增强材料,以RTM工艺制备了2.5D编织碳纤维增强RTM酚醛树脂烧蚀材料,研究其孔隙率、层间剪切强度等性能。研究结果表明,高成碳RTM酚醛树脂800℃成碳率达到67.05%,80℃树脂起始粘度213.0 m Pa·s,工艺适用期120 min,满足烧蚀材料RTM制备工艺要求,所制得2.5D碳纤维编织/酚醛烧蚀材料孔隙率不超过2.94%,层间剪切强度达到59.2 MPa,层间性能显著优于传统二维碳纤维织物铺层增强酚醛树脂复合材料。展开更多
为深入研究干馏瓦斯在金属管内的积碳特性,采用自制的连续流动反应装置,以06Cr25Ni20不锈钢管为反应器,对不同温度(600,650,700,750℃)、不同反应时间(30,60 min)、不同气体流量(10,20 m L/min)等条件下干馏瓦斯在反应器内的积碳特性进...为深入研究干馏瓦斯在金属管内的积碳特性,采用自制的连续流动反应装置,以06Cr25Ni20不锈钢管为反应器,对不同温度(600,650,700,750℃)、不同反应时间(30,60 min)、不同气体流量(10,20 m L/min)等条件下干馏瓦斯在反应器内的积碳特性进行了试验研究,得出了瓦斯气初始积碳的温度区间为450~470℃;通过程序升温氧化方法,结合扫描电子显微镜对积碳的微观形态进行分析,分析结果显示积碳中有两种不同类型的焦炭,即无定型碳和纤维焦炭;用能谱分析剥离下来焦炭的结果显示,焦炭中含有质量分数为15.574%,4.463%,17.283%的铬、镍、铁原子,说明金属发生了渗碳现象;运用气象色谱仪对不同试验前后瓦斯气体的组分进行分析,从分析结果可以看出小分子烯烃为主要的成碳物质。展开更多
A study of the interfacial behavior and internal thermal stress distribution in fiber-reinforced composites is essential to assess their performance and reliability.CNT/carbon fiber(CF)hybrid fibers were constructed u...A study of the interfacial behavior and internal thermal stress distribution in fiber-reinforced composites is essential to assess their performance and reliability.CNT/carbon fiber(CF)hybrid fibers were constructed using electrophoretic deposition.The interfacial properties of CF/epoxy and CNT/CF/epoxy composites were statistically investigated and compared using in-situ thermal Raman mapping by dispersing CNTs as a Raman sensing medium(CNT_(R))in a resin.The associated local thermal stress changes can be simulated by capturing the G'band position distribution of CNT_(R) in the epoxy at different temperatures.It was found that the G'band shifted to lower positions with increasing temperature,reaching a maximum difference of 2.43 cm^(−1) at 100℃.The interfacial bonding between CNT/CF and the matrix and the stress distribution and changes during heat treatment(20-100℃)were investig-ated in detail.This work is important for studying thermal stress in fiber-reinforced composites by in-situ thermal Raman mapping technology.展开更多
文摘针对树脂传递模塑工艺(RTM)对于可用树脂的要求,研究了适用于RTM工艺的高成碳RTM酚醛树脂的相关性能,表征了高成碳RTM酚醛树脂的分子结构,分析了树脂的流变特性、树脂成碳率以及RTM工艺适用性。为了进一步制备层间性能优异的树脂基烧蚀材料,选用2.5D碳纤维编织预制体为增强材料,以RTM工艺制备了2.5D编织碳纤维增强RTM酚醛树脂烧蚀材料,研究其孔隙率、层间剪切强度等性能。研究结果表明,高成碳RTM酚醛树脂800℃成碳率达到67.05%,80℃树脂起始粘度213.0 m Pa·s,工艺适用期120 min,满足烧蚀材料RTM制备工艺要求,所制得2.5D碳纤维编织/酚醛烧蚀材料孔隙率不超过2.94%,层间剪切强度达到59.2 MPa,层间性能显著优于传统二维碳纤维织物铺层增强酚醛树脂复合材料。
文摘为深入研究干馏瓦斯在金属管内的积碳特性,采用自制的连续流动反应装置,以06Cr25Ni20不锈钢管为反应器,对不同温度(600,650,700,750℃)、不同反应时间(30,60 min)、不同气体流量(10,20 m L/min)等条件下干馏瓦斯在反应器内的积碳特性进行了试验研究,得出了瓦斯气初始积碳的温度区间为450~470℃;通过程序升温氧化方法,结合扫描电子显微镜对积碳的微观形态进行分析,分析结果显示积碳中有两种不同类型的焦炭,即无定型碳和纤维焦炭;用能谱分析剥离下来焦炭的结果显示,焦炭中含有质量分数为15.574%,4.463%,17.283%的铬、镍、铁原子,说明金属发生了渗碳现象;运用气象色谱仪对不同试验前后瓦斯气体的组分进行分析,从分析结果可以看出小分子烯烃为主要的成碳物质。
文摘A study of the interfacial behavior and internal thermal stress distribution in fiber-reinforced composites is essential to assess their performance and reliability.CNT/carbon fiber(CF)hybrid fibers were constructed using electrophoretic deposition.The interfacial properties of CF/epoxy and CNT/CF/epoxy composites were statistically investigated and compared using in-situ thermal Raman mapping by dispersing CNTs as a Raman sensing medium(CNT_(R))in a resin.The associated local thermal stress changes can be simulated by capturing the G'band position distribution of CNT_(R) in the epoxy at different temperatures.It was found that the G'band shifted to lower positions with increasing temperature,reaching a maximum difference of 2.43 cm^(−1) at 100℃.The interfacial bonding between CNT/CF and the matrix and the stress distribution and changes during heat treatment(20-100℃)were investig-ated in detail.This work is important for studying thermal stress in fiber-reinforced composites by in-situ thermal Raman mapping technology.
