碳纤维复合材料气瓶的X射线实时成像技术

针对某型号卫星用碳纤维复合材料气瓶的结构特点,分析了其常见缺陷及其对复合材料性能的影响,运用射线实时成像技术进行在线动态检测,取得了较好的效果.     

自蔓延高温合成MgO-B4C微观组织研究

B2O3-Mg-C体系的SHS过程中,由于还原剂Mg的蒸气压较高,因此它与B2O3之间的反应不可避免地受到环境中惰性气体压力的影响,研究发现,不同气压下产物的晶粒尺寸与形貌不同,气压分别为101．3Kpa和10．1MPa时,产物B4C的粒径相应为0．4um和5um。     

树脂基复合材料蜂窝夹层结构的修补技术

为了降低复合材料制造成本以及延长复合材料的使用寿命,其修补技术是不可缺少的。本文根据不同修补方法和材料体系对修补试件进行研究,并对材料修补后的试件强度和母板强度作了比较,结果证明有关复合材料蜂窝结构件受损后的修补问题得到了有效地解决。     

Uncertainty evaluation for bearing fatigue property of CFRP double-lap,single-bolt joints

The considerable uncertainty in mechanical properties of composite bolted joints not only prevents advanced composite materials from efficient applications, but also threatens the safety and reliability of the aircraft structures. In this paper, the uncertainty in bearing fatigue properties of a CFRP double-lap, single-bolt joint was evaluated by combing a Progressive Fatigue Damage Model(PFDM) with the interval analysis method. In the PFDM, a residualstrain-based gradual material degradation mo...     

Integrated design of topology and material for composite morphing trailing edge based compliant mechanism

The morphing trailing edge based compliant mechanism is a developing technology which can increase lift-drag ratio for variable flight modes by bending down the trailing edge. Composite material design is integrated into topology optimization for the morphing trailing edge based compliant mechanism in the paper. A two-step optimization strategy is established to solve the integrated design problem. Initially, lamination parameters are introduced and viewed as a bridge between structure stiffness and fiber angles for composite material. Design variables include the lamination parameters and element density. The least-squares between actual and desired displacements at output points along trailing edge is adopted to evaluate the deformed capability of the trailing edge. An integrated optimization model for the composite morphing trailing edge is established with the volume constraints. The optimal topologic shape and lamination parameters are initially obtained. Subsequently, a least-squares optimization between fiber angles and the optimal lamination parameters is implemented to obtain optimal fiber angles. Finally, morphing capability of composites trailing edge based compliant mechanism is investigated by simulation and experiments. The results indicate the composites trailing edge based compliant mechanism can approximately bend down 8 degrees and satisfies the design requirement.     

树脂基复合材料孔隙率超声表征技术研究

利用超声衰减的原理,运用超声C-扫描成像技术超声表征评定树脂基复合材料的孔隙大小,进而评定材料的力学性能情况,结合解剖试验建立了树脂基复合材料超声衰减、孔隙率和力学性能的关系曲线,探索了一种超声表征评定树脂基复合材料的孔隙情况及力学性能的方法.     

国产芳纶纤维复合材料用环氧树脂体系

研制了一种环氧/ 芳香胺体系,采用DSC、固化反应动力学分析等方法对树脂体系进行了表征,并
对其浇注体、复合材料NOL 环以及Φ150 mm 压力容器性能进行了研究。结果表明,该树脂体系具有优良的浇
注体力学及热性能,其拉伸强度为101 MPa,断裂伸长率达4. 1%,弯曲强度为177 MPa,马丁耐热温度为
142． 2℃;与国产芳纶纤维的界面粘接性能良好,其NOL 环层间剪切强度可以达到52. 1 MPa,制备的复合材料
Φ150 mm 压力容器PV / W 值可达38. 44 km。     

纤维结构对EPDM 复合材料性能的影响

对比了聚酰亚胺纤维、芳砜纶、芳纶纤维的热稳定性,并分别以这三种纤维为增强体,制备了短纤
维填充的三元乙丙(EPDM)热防护复合材料,对该材料的耐烧蚀性能、碳化层结构、力学性能以及纤维在橡胶
中的分散性进行了研究,结果表明聚酰亚胺纤维具有比芳砜纶、芳纶纤维更高的热稳定性和残碳率,由其填充
的EPDM 复合材料耐烧蚀性能最好,烧蚀深度为0. 8 mm。纤维在橡胶中的分散性与纤维结构有关,进而影响
复合材料的力学性能以及碳化层结构特性。     

周边封闭铝蜂窝夹层结构配合改进和胶接工艺研究

采用多种材料作为校验膜测试零件间的配合间隙,分析对比使用效果确定了最佳校验材料。对柔性蜂窝芯零件的周边加强和定位进行了研究,在蜂窝芯边缘和倒角区采用泡沫胶修形,改善零件间的配合关系。为提高板_板区的胶接质量,采用自制压条使板_板胶接区平整,且满足了无损检测的要求。     

复合材料斜面压铆和锤铆铆接质量对比分析

通过试验对复合材料斜面机器压铆和手工锤铆两种铆接方法的质量进行评估。评估内容主要包括铆钉的外观质量、复材铆接件的外观质量、无损检测和力学性能测试4个部分。结果表明:压铆的铆钉比复材铆接件的外观质量更好,受人为因素影响小;在无损检测后,压铆后的复材铆接件没有出现分层现象;在力学性能测试部分,压铆的铆接强度优于锤铆的铆接强度。可见在复合材料铆钉中压铆更具有实用性和适用性。