Hybrid impact resistance

Hybrids of block copolymer rubbers and acrylics have also been used to increase the low-temperature impact resistance of the adhesive used for body-side molding attachment [127]. To further enhance performance, a new type of hybrid adhesive has been developed, which combines an adhesive polymer, like an... 

HTPC (Hybrid ThermoPlastic Composite) bumper beams made by Plastic Omnium are used by General Motors on the Pontiac Montana, Chevrolet Venture and Oldsmobile Silhouette. Continuous woven fibres are overmoulded with a long or short fibre reinforced polypropylene to save weight (6 kg), enhance impact resistance (20-40%) and integrate numerous functions such as reinforcement ribs. The process is fully automated. 

A good example of a flexible epoxy hybrid adhesive is the epoxy polysulfides. Figure 8.2 shows the improved impact resistance that can be realized by using increasing amounts of... 

The parametric curves in Figures 6.8 to 6.11 can be used individually to select hybridization ratios to satisfy a particular design requirement or they may be used jointly to satisfy two or more design requirements simultaneously, for example, frequency and impact resistance. Comparable plots can be generated for other structural components, such as plates or shells. Also plots can be developed for other behavior variables (local deformation, stress concentration, and stress intensity factors) and/or other design variables, (different composite systems).This procedure can be formalized and embedded within a structural synthesis capability to permit optimum designs of intrapiy hybrid composites based on constituent fibers and matrices. 

Delphi Automotive Sj ems, Woodridge, IL and Hendrickson Innovations International developed and manufactured a plastic composite (glass/ carbon fiber hybrid reinforcement) for use in the medium and heavy duty truck and bus markets. When compared to metals they are lighter and more impact resistant, require less mounting hardware, and designed to conduct 50% less vibration. 

Milwich et al. (2006) combined ideas of cellulose fiber orientation in wood with the structure of the stem of giant reeds to create a hybrid model realized using advanced braid protrusion machinery at the Institute of Textile Technology and Process Engineering (ITV) Germany. The outcome called Technical Plant Stem is a commercially scalable architectural textile composite that demonstrates excellent strength and impact resistance with the minimal material use (Speck and Speck, 2006). 

Peijs A, Venderbosch RW, Lemstra PJ, Hybrid composites based on polyethylene and carbon-fibres, 3. Impact resistant structural composites through damage management, Composites, 21(6), 522-530, 1990. 

With carbon reinforcements, it is possible to incorporate two or more different yarns (e.g. an aramid and carbon, or glass and carbon), to form a hybrid carbon reinforcement, enabling a designer to incorporate properties into a composite that fall between the performance levels of the chosen fibers. So the introduction of an aramid fiber into a carbon fabric reinforcement would improve the impact resistance, albeit at the expense of other mechanical properties. Special scissors are available to cut aramid fibers. 

Lincoln Composites manufacture a range of on board vehicle tanks for CNG. The tanks are made by overwrapping a polymeric liner such as polyethylene with a composite and a hybrid mix of glass and carbon fiber is used to improve impact resistance. 

Thanomsilp, C., Hogg, P., 2003. Praietration impact resistance of hybrid composites based on commingled yam fabrics. Compos. Sci. Technol. 63, 467-482. 

Fibres are used mainly in the form of short or long chopped filaments/strands. mats made of random chopped strands, or woven fabrics of varying density. Woven and non-woven fabrics can be used to improve. surface qualities such as appearance, impact resistance, abrasion, and chemical resistance. To improve distribution and orientation of fibres in a three-dimensional moulding, there has been considerable development of preforming techniques, and machine-made three-dimensional arrangements of fibre, which offer better drape in a mould. When more than one fibre is used, the composite is termed a hybrid. 

The major advantages of these UV-curable hybrid systems lie in their superior combination of properties which can be tailor-made for a given application by adjusting the proportions of the two components. The IPN formed will exhibit the main features of the two polymer networks, for instance the toughness and scratch resistance of UV-cured acrylate polymers and the elastomeric character of the cross-linked polyurethane-vinyl ether, with the expected benefit regarding adhesion and impact resistance. 

A preaccelerated, flexible high performance laminating urethane acrylate hybrid resin, particularly suited to high deflection applications, with high impact resistant properties. Offers excellent adhesion to both glass and aramid fibres which benefits interlaminar shear properties. 

A preaccelerated, thixotropic, tough, impact resistant laminating urethane acrylate hybrid resin, designed for high performance applications, but with the ease of use of a polyester. Approved by Lloyd s Registry. 

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