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为了表征当前火箭发动机工业中常用的一些壳体复合材料特性,我们做了大量的工作。本文介绍了工作的结果,并且特别注意到了这样一个事实,即这些纤维缠绕材料是在固化炉中固化的,与“飞机”型在热压釜中固化的铺层方法比较,此方法对材料的力学性能会有影响。本文涉及到的所有试样都是从纤维缠绕的样品中取得的。 本研究的目的是评价和鉴定具有当前水平的表征试验方法:测定纤维取向的作用、试验方法和温度对性能的影响;表征复合材料有限元分析中用的所有正交各向异性弹性常数的特性;建立测预和实测性能间的关系;确定今后努力的方向。 我们对四种材料系统进行了表征,它们是:凯夫拉49、涂复有DC-20松粘剂的凯夫拉49、S-2玻璃和341型S-2玻璃布。环氧系统是“刚性”酸酐双酚A环氧,其杨氏模量为2827MPa。凯夫拉试样的准备工作有一些困难,为了获得合适的样品,不得不采用优于高压水喷射或传统机加的激光切割,但在切割涂复有松粘剂的凯夫拉时仍有问题,因为这种材料的层间强度很低。 板片状和环向缠绕环的拉伸试验给出了相当的数据,而且获得了与纤维取向有关的刚性变化和传统叠层理论二者之间极好的相关性。对用各种剪切方法获得的数据进行了比较,它表明与轴线成10°的叠层较之环向缠绕管状试样,其剪切模量高,但剪切
In order to characterize some of the shell composite materials currently used in the rocket engine industry, we have done a great deal of work. This paper presents the results of the work and notably notes the fact that these fiber-wound materials are cured in a curing oven compared to the “airplane” type of lay-up that cures in an autoclave, Mechanical properties will have an impact. All of the samples covered in this paper were taken from the fiber-wound samples. The purpose of this study was to evaluate and characterize current state-of-the-art characterization test methods: determining the effect of fiber orientation, test methods and temperature on performance; characterizing all orthotropic elastic constants used in finite element analysis of composite materials ; Establish the relationship between measurement and measurement performance; determine the direction of future efforts. We characterized four material systems: Kevlar 49, Kevlar 49, S-2 glass and 341 S-2 glass cloth coated with DC-20 release agent. The epoxy system is a “rigid” anhydride bisphenol A epoxy with a Young’s modulus of 2827 MPa. There are some difficulties with the preparation of Kevlar samples, which have had to be laser-cut better than high-pressure water jets or traditional mills in order to get the right samples, but still have problems with cutting Kevlar with a tackifier Because of the low interlaminar strength of this material. Tensile tests on lamellar and toroidal wound rings gave comparable data and obtained excellent correlation between the change in stiffness associated with fiber orientation and the traditional lamination theory. Comparisons of the data obtained with the various shear methods show that the stack at 10 ° to the axis has a higher shear modulus than the hoop-wrapped tubular sample but shear