Reinforced-plastic resin transfer

This decay rate is nearly equivalent to that exhibited by one g of radium in equilibrium with its disintegration products. A miUicurie (mCi) is 0.001 curie, curie point See magnetized curie point, curing See autoclave nitrogen atmosphere cure extruder wire and cable process, dry cure inhibitor prepreg volatile content reinforced plastic resin transfer molding test, Barcol hardness test, scorch Mooney thermoset plastic vulcanization welding, induction. 

Resin transfer molding With vacuum assisted RTM, this process can be called infusion molding. RTM usually uses liquid TS plastics that is transferred or injected into an enclosed mold usually at low pressures of about 60 psi (410 kPa) in which reinforcement... 

SCRIMP process This Seeman Composites Resin Infusion Process (SCRIMP) is described as a gas-assist resin transfer molding process. As an example glass fiber fabrics/ thermoset vinyl ester polyester plastic and polyurethane foam panels (for insulation) are placed in a segmented tool. A vacuum is pulled with a bag so that a huge amount of plastic can be drawn into the mold (Marco process approach). Its curved roof is made separately and bonded to the box with mechanical and adhesive fastening. It is similar to various reinforced plastics molding processes. 

The mold in RRIM is similar to resin transfer molding (RTM) (Chapter 15). In the reinforced RIM (RRIM) process reinforcements such as woven or nonwoven fabrics, short glass fibers, glass flakes, milled fibers dry reinforcement preform, etc. are placed in a closed mold. Next a reactive plastic system is mixed under high pressure in a specially... 

Ultem . [GE nasties GE Plastics Ltd.] Pcdyedietimide resins, stnne glass or mineral reinforced thermoidastic resin for laboratory ware and antunodve heat transfer systems, elec./electronic sqridics., computer circuitry, microwave conq>onenis, molded parts, electronic housings, structural components, EMI/ RH/ESD rqqdics. m aircraft imtotry. 

Fibers in RPs are primarily used to reinforce a resin by transferring the stress under an applied load from the weaker resin matrix to the much stronger fiber. Plastics provide valuable and versatile materials for use as matrices, but other materials, such as metals, ceramics, and cements, are... 

RTM was described May 1957 (at the BPF Reinforced Plastics Conference), in a paper on work dating from 1954 at Bristol Aircraft, Filton, UK. It is basically a liquid resin version of compression transfer molding a process in which a charge of compound is placed in a transfer pot and is injected into a closed mold, usually by a plunger system. The method allows the compound to be suitably prepared melt and then transferred fast and accurately into the mold, in which the required reinforcement has already been placed, in suitable form. 

Chrysler specified a modified polymethyl methacrylate (PMMA) laminating resin for the body panels of the high-performance sports car, the 400 bhp 10 cylinder Dodge Viper, which went on sale in January 1992. The transition from styling to production took only three years. The decision to use glass fiber reinforced PMMA resin, molded by resin transfer, was a fundamental departure from established Chrysler practice, where previously all main exterior bodywork had been in sheet metal. However, at expected sales of 3000 a year and a unit price of about 50,000, sheet metal would not have been viable and the annual volume was too low to justify injection or compression molded plastics. 

The same trends can stiU be observed in fibre reinforced plastics, although the reinforcement will moderate the changes in mechanical properties. However, there are other possibilities, such as glass fibre-resin debonding, caused by water absorption from aqueous liquids. This can mean a reduction in translucency. Load transfer between fibres is also less effective. Carbon fibres, in contrast, are unaffected by water below 1000°C. 

Marsh G, Process refinement key to RTM success. Reinforced Plastics, 26 30, Feb 1999. Benjamin W, Beckwith S, Resin Transfer Molding (RTM) Technologies, SAMPE Monograph 3. SP Systems, Composite Engineering Materials Product Information Handbook Guide to Composites, Newport, lOW. 

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