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Constituent Materials
Published in B. T. Åström, Manufacturing of Polymer Composites, 2018
Naturally the characteristics of a honeycomb core significantly depend on its constituents, but also on cell configuration and wall thickness. The predominant advantage of honeycomb cores is their excellent specific mechanical properties since their density is so low. Disadvantages include moisture sensitivity, difficult machining, difficult bonding of faces, and high price. Temperature sensitivity and drapeability may be good or poor depending on core material and cell configuration. Cores manufactured through the expansion and corrugation methods have two perpendicular inplane directions with significantly different properties, since the bonding procedure creates double cell walls along the bond lines. The direction of the core containing the double cell walls is called the length direction and the direction perpendicular to it is consequently the width direction.
Hypersonic Aircraft
Published in G. Daniel Brewer, Hydrogen Aircraft Technology, 2017
The second structural concept, shown at the bottom of Figure 5–26, is an integral thermal insulation/tank structure which is made of a honeycomb sandwich with the core evacuated to provide the necessary insulative properties. Several different materials are candidates to be used for the honeycomb structure: titanium alloys, advanced powder metallurgy aluminum alloys, aluminides, and metal-matrix composites. Facesheets can be attached to the core by low temperature brazing or by adhesive bonding. Panels made of the resulting honeycomb structure would be welded together to form a structurally efficient, cryogenic fuel containment vessel.
Fibre-reinforced composite materials
Published in William Bolton, R.A. Higgins, Materials for Engineers and Technicians, 2020
Honeycomb panels are rather like corrugated cardboard, but the sandwiched layer has a honeycomb structure instead of corrugations (Figure 24.7). The honeycomb cells are generally hexagonal in shape. Honeycomb materials are useful where flat or slightly curved surfaces are needed with a high specific strength, and are widely used in the aerospace industry.
Research on out-of-plane impact characteristics of self-similar gradient hierarchical quasi-honeycomb structure
Published in International Journal of Crashworthiness, 2022
Xiang Li, Mingjie Cai, Ruibo He, Xingxing Xu
With the increasing attention to the passive safety protection of structures in the engineering field, the collision problem has become an important topic in engineering field. The research on the dynamic behavior of structures during collisions and design energy absorbing buffer structures with higher impact resistance has great significance in engineering. Honeycomb structure has many characteristics, such as lightweight, high specific strength, high specific stiffness and excellent energy absorption, widely applied in aerospace, automobile and ship, armor protection and other important fields. Therefore, it is very urgent to study honeycomb impact characteristics. At present, hexagonal honeycomb structures [1], square honeycomb structures [2] and triangular honeycomb structures [3] are the most common honeycomb structures in the engineering field, which usually consist of a single type of cellular elements arranged periodically.
Three-dimensional phase field modeling of progressive failure in aramid short fiber reinforced paper
Published in Mechanics of Advanced Materials and Structures, 2022
Song Zhou, Tong Wang, Xiaodi Wu, Zhi Sun, Yan Li, Filippo Berto
As a kind of synthetic aromatic polyamide, aramid fiber has many outstanding properties, such as high strength, high modulus, low density, good insulation, high temperature and corrosion resistance [1–6]. Aramid fiber can also be used to make short fiber reinforced composite paper which can then be used to make the honeycomb with significant mechanics performances. In the modern industries such as aerospace, defense, communication, the honeycomb is widely used in varies structures [7, 8]. For this reason, the short aramid reinforced paper with higher properties which play the key roles of the performance of honeycomb are desired [9–12]. Among the common properties, the overall strength is of particular concern [13]. Progressive failure modeling of composites plays an important role in providing important tools in the design of the safety and stability [14–18]. However, the complicated microstructure of aramid fiber composite paper may result in multiple failure mechanisms, such as fiber breakage, matrix cracking, fiber debounding, and thus posing challenges to the modeling techniques. The interaction among so many cracks has posed challenges to existing numerical methods, such as the widely used cohesive model based extended finite element method (XFEM) [19]. Another challenge when modeling progressive failure from microscopic length scale is that the model size could be huge. So far, many classic damage models are confined to small sized models and the modeling consumed time could be unacceptable when a large sized model is considered.
Review of Heat Exchangers Enabled by Polymer and Polymer Composite Additive Manufacturing
Published in Heat Transfer Engineering, 2018
David C. Deisenroth, Ramin Moradi, Amir H. Shooshtari, Farah Singer, Avram Bar-Cohen, Michael Ohadi
The silicon carbide and carbon fiber reinforcements were used for structural enhancement for their high strength and stiffness. For this reason, the aligned nature of the strong fibers in the printed honeycomb-type structures showed outstanding ratios of stiffness and strength to density, far outperforming conventional polymer additive manufacturing methods, and approaching the strength to weight and stiffness to weight ratios of balsa wood. A key advantage to honeycomb structures is that they could provide high volumetric heat transfer coefficients, due to high surface area per volume [60]. Next, the reported literature on heat exchangers constructed with the use of PAM will be presented.