Metals replacement, applications

RPs have already been used in different structural applications, to replace conventional metal in seawater-compressed air surfacing ballast tanks in the Alvin depth vehicle. This vehicle, a first-generation deep research vehicle, also used RP in its outer hull construction to enclose the pressure tanks and aluminum frame. In the unmanned acoustical research vehicle of the Ordnance Research Laboratory called Divar, an RP cylinder with a 16 in. OD, 3/4 in. wall thickness, I2V2 in. ID with nine ribs, a 60 in. length and weight of 180 pounds went to depths of 950 m (6,500 ft.). 

Since 2004 [183], graphene research has evolved from a heavily theoretical and fundamental field into a variety of research areas [301]. Its electrical, magnetic, physical-mechanical, and chemical properties position it as the most promising material for molecular electronic and optoelectronic applications, possibly replacing the currently used silicon and metal oxide based devices. Nonetheless, further research is essential in order to control easily such properties and construct devices with specific and novel architectures to explore in depth all of these exciting properties, as well as to achieve the synthesis of large-scale, size- and layer-count controlled graphene. 

Application development for phenolics has been spurred by weight and cost savings inherent in metal replacement and parts consolidation. Thermoplastics have been replaced by phenolics where creep resistance and thermal stability are required in downsized parts or applications in hostile environments. 

There is increasing interest in the application of reinforced plastics for metal replacement in the automotive industry to reduce weight and cost. In some applications, reinforced plastics also oner performance advantages over metal. Although the automotive industry is greatly depressed at the present time, a recent report indicates an 11.6% annual growth rate for reinforced plastics in cars and trucks in the next five years (8). 

The first applications were those requiring autoclaving (medical equipment) or outstanding electrical properties at elevated temperatures. As compounding, stabilization, and processing skills improved, markets for Noryl expanded to Include office equipment, electronic components, automotive parts, water distribution systems, and general metal replacement. 

Such glass fiber-reinforced composites based on the unsaturated polyester thermosets are usually fabricated as sheet molding compounds (SMC) and bulk molding compounds (BMC). These are widely used in various metal replacement applications because of their cost-effectiveness, rigidity, light weight, and corrosion resistance properties particularly useful in transportation (cars and trucks), constmction, pipe, and tank applications. Automotive and tmck body panel and strucmral component applications of SMC include doors, hatchbacks, hoods, front grilles, etc. Some nonautomotive applications of SMC and BMC include sanitaryware (bathtubs, shower stalls, sinks), appliances, business machine, and electrical components. 

Polyester resin moulding compound Pipe joints, guards, metal replacement, high strength applications Good electrical performance ... 

Structural foam parts have the combination of performance properties and process features that dehver increased stiffness to weight ratio. Hence they are suitable for metal replacement in some applications. 

Though multiple-path load-bearing applications abound in aerospace structures, composites generally have not yet been effective (due to weight or cost) in replacing metal in these applications. Metal s ability to have the same internal element carry a load in several directions at once, as it is isotropic, is very hard to beat and equally hard... 

Polyamides were the first engineering plastics and still represent by far the biggest and most important class of these types of material. The combination of mechanical and thermal properties allows them to be employed for highly specified end uses and often for metal replacement applications (see Engineering Thermoplastics, Survey). 

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