Plastic/metal hybrids

Plastic Metal Hybrid Structural Roof Frame on 2005 Audi A6 made of Durethan BKV30 H2.0, a 30% glass fibre reinforced PA 6 from Lanxess, provides a 30% weight saving. 

Also molded are unreinforced or RP to metal hybrids. Plastic-metal hybrids are replacing all-steel structures in automotive front end modules at an accelerated rate. Technical approaches to hybrids are multiplying as more resin suppliers develop alternatives to the overmolding method first established by Bayer. Tier One automotive part suppliers, while tight-lipped on their plans, are also working on proprietary hybrid concepts. 

Modem dashboard constmctions are based on a supporting structure made of sheet metal, a plastic-metal hybrid, fiber-reinforced thermoplastics (GMT [PP]) or dur-oplastics (SMC [UP], SRIM [PUR]). 

Plastic-Metal Hybrids Make Headway On and Off the Road, MP, Dec. 2003. 

Prototypes for modular design of plastic-metal hybrid components have resulted in modular front-end component implementation on the 1996 European Ford Focus, the 1999 North American Ford Focus, the 1994 Audi A6, and 1997 Audi A2. The concept utilizes an injection-molded nylon housing overmolded onto a steel frame, which encompasses (he modular front end. Other applications of such technology have been extended to seats, being incorporated into the 1992 Mercedes-Benz Viano seat. 

Several producers such as Bayer, Dow (LFT-PP concept) and Rhodia (PMA - Plastics Metals Assembly, and MOM - Metal Overmoulding - processes) have developed their own hybrid technologies. 

The best performance/density/cost compromise giving the best cost with the lowest weight and sufficient performance levels to meet the requirements. Plastic/metal or plastic/wood/metal hybrid materials are sometimes excellent solutions. 

Another important application area is the non-destructive defectoscopy of electronic components. Fig.2a shows an X-ray shadow image of a SMC LED. The 3-dimensional displacement of internal parts can only be visualized non-destructively in the tomographic reconstmction. Reconstructed cross sections through this LED are shown in Fig.2b. In the same way most electronic components in plastic and thin metal cases can be visualized. Even small electronic assemblies like hybrid ICs, magnetic heads, microphones, ABS-sensors can be tested by microtomograpical methods. 

The best replacement for borosilicate glassware is stainless steel. Stainless steel takes the heat, won t break, and, most importantly, is about as resistant to chemical degradation as the chemist can hope to find. For those items that won t be subjected to direct heat there can be some steel/metal or steel/plastic hybrids. In figure 3 is shown how flasks of any size can be made with two stainless steel mixing bowls welded together. Also shown is the vacuum adaptor and condenser. For the condenser only the inner pipe need be steel. The outside pipe can be copper or something. As for the other components of a distillation set up, well, they are made just as they look. 

The hybrid techniques often associate polymers and metals and combine the benefits of the two material classes. The metal provides the rigidity and the overmoulded reinforced plastic keeps the shape of the metal and adds numerous functionalities. 

Hybrids combine plastics or composites with other materials such as metal, wood, etc. Plastics filled with talc or other powders are not taken into account in this chapter. 

The combination of simple processes from plastic and metal technologies. Each material has its advantages and drawbacks. Hybrids that closely associate two or more families benefit from their best properties and mask their weaknesses. 

Use of hybrids of plastics and metals or other conventional materials. 

Plastics. Part of the trend to substitute plastic and composite substrates for metals can be attributed to a desire to avoid the process of metallic corrosion and subsequent failure. Relatively little attention has been called to the possible failure modes of plastics under environments considered corrosive to metals. More extensive work should be conducted on the durability and life expectancy of plastic and composite materials under end-use environments. A further consideration is the potential for polymer degradation by the products of metal corrosion in hybrid structures comprising metal and polymer components. Since it is expected that coatings will continue to be used to protect plastic and composite substrates, ancillary programs need to be conducted on the mechanisms by which coatings can protect such substrates. 

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