Multi-material

Multi-Material Injection Moulding, V. Goodship and J.C. Love, The University of Warwick. 

New ways to recycle complex multi-material packaging systems. 

Shock-induced Chemical Reactions in Heterogeneous Multi-Material Powder Mixtures. 

Ube developed the PA nanocomposite named Ecobesta to replace PVDF or other traditional barrier materials. The all-polyamide structure offers recycling advantages compared to traditional multi-materi designs. It incorporates ... 

Sequential EBM is a special multi-material technique used for the production of special designed products. The different plastics are chosen typically to contribute complementary mechanical properties and are present in distinct sequential zones in the finished part. Normally two materials are used but three or more are also used. Separate external ram accumulators for each material serve the die head. These are operated sequentially, typically in A-B-A sequence, to produce a parison with three distinct material zones in axial succession. The parison is subsequently BM by normal techniques. 

Multi-layer products that can still be classified as plastic for food contact as the food contact layer consists of plastic, but that contain other types of materials such as adhesives, aluminium foils, paper, etc. These materials are often referred as multi-material multilayers. 

Youngs, D. L., Time-dependent multi-material flow with laige fluid distortion. In Numerical Methods for Fluid Dynamics (K. W. Morton and M. J. Baines, eds.). Academic Press, New York, 1982, p. 273. 

Edited by K. Kussmaul, D.L. McDiarmid and D.F. Socie ESIS 11 Mechanics and Mechanisms of Damage in Composites and Multi-Materials... 

Postconsumer materials (recycling and urban mining) complex, multi-material, metal-containing products (for example hybrid electric vehicles). 

In general, when two or more different types of polymer are mixed, they show immiscibility (separation of phases), and exhibit a dispersion of the minor phase (the dispersed phase) in the major phase (the matrix). The cohesion between these different phases is low in most cases, and so the mechanical performances of the blends produced by simple blending are generally low, and need improvement. This is of prime importance in the preparation of mnlti-layered prodncts (packaging films, bottles, and so on) or multi-material parts, as well as where plastics are reinforced by fillers or by fibres. In such cases, interfacial cohesion between different phases can be improved by the use of special additives, called adhesion promoters or compatibilisers, that act at inter-phases. 

Mohamed G, Soutis C, Hodzic A. Multi-material Arbitrary-Lagrangian-Eulerian formulation for blast-induced fluid-stmcture interaction in fibre metal laminates. AIAA J Am Inst Aeronaut Astronaut Struct Mech Mater 2012 50(9) 1826—33. 

Lund E. Buckling topology optimization of laminated multi-material composite shell structures. Compos Struct 2009 91 158-67. 

Goodship, V. Love, J. C., Multi-material Injection Moulding, Rapra, Shawbury, 2002. 

The affirmation of the importance of the welded joints in questions regarding reactor lifetime especially during creep conditions which must lead to an increased R D effort bzised on the methods adapted to their local aspect and multi-materials. 

Colorants can make relatively cheap commodity materials such as POs appear to be (superficially at least) more than just the sum of their parts. POs have relied on their colorability to make products more aesthetically pleasing to use, or simply to draw more visual attention toward a product. Product differentiation is perhaps the main reason POs are colored, whether for short-lived packaging or for color-matched, durable, multi-material assemblies such as automobiles and playground equipment. 

Looking further ahead, the recent development of multi-material AM could have a significant impact upon customised footwear and handwear systems. In a single build process, the Connex series of machines (Objet Geometries, 2010) can build a component (or assembly of components) from a combination of materials, ranging from a soft flexible rubber to a stiff plastic. In theory, this would enable a flexible skin to be produced with embedded protective elements that conformed to the shape of the hand or foot. However, the rubber-like nitrile-based materials currently available have a low tear resistance, which makes them unsuitable for repeated bending and flexing. Nevertheless, future materials development could yield improved characteristics, so this is an area worthy of future research effort. 

If the required characteristics of a product are not achievable using but one material, multi-material composite systems are necessary. Systems containing separable composites need to be disassembled prior to recycling, which can be done manually or by machine. This is what happens, for example, to non-textile functional elements used within garments, and to technical textiles. 

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