Vacuum molding

PROCESS WATtR CONTAINER SCRAP 1 VACUUM MOLD FLLUV SJRCS Pt AS7IC... 

One typical example of carbon/carbon composite plates is that made by Oak Ridge National Laboratory (ORNL) in the United States [12]. The composite preform was fabricafed by a slurry-molding process from fhe mixed slurry befween short carbon fibers (graphite fibers were also added in some sample plates) and fhe phenolic resin. The mass rafio between fiber reinforcement and phenolic matrix is 4 3. The phenolic matrix improves the mechanical properties and dimensional stability of the plate. A subsequent vacuum molding process was utilized to fabricate composite plates and fluid fields with relatively high resolution (Figure 5.3, [11]). 

Whiskers can be incorporated into the metallic matrix using a number of compositeprocessing techniques. Melt infiltration is a common technique used for the production of SiC whisker-aluminum matrix MMCs. In one version of the infiltration technique, the whiskers are blended with binders to form a thick slurry, which is poured into a cavity and vacuum-molded to form a pre-impregnation body, or pre-preg, of the desired shape. The cured slurry is then fired at elevated temperature to remove moisture and binders. After firing, the preform consists of a partially bonded collection of interlocked whiskers that have a very open structure that is ideal for molten metal penetration. The whisker preform is heated to promote easy metal flow, or infiltration, which is usually performed at low pressures. The infiltration process can be done in air, but is usually performed in vacuum. 

Most epoxy syntactic foams are vacuum molded at 70-120 °C, and vibrating stirrers are used to degas the mixture40 . Recent formulations can be processed without external heating (cured for 30 days at 20 °C) and yet yield syntactic foams with properties comparable to those of hot-cured foamsthe shrinkage is less than 1 % for both. 

These special fabrics plus information on various laminating and vacuum molding techniques are available from WA Clark, the leading supplier to the white water boat trade.(see figure 6) When contacting or ordering from Clark, be sure to specify that the materials are for boat or kayak... 

The pharmaceutical BFS process combines the formation of plastic containers by blow/vacuum molding extruded pharmaceutical grade polymers, with an aseptic solution filling system. 

Small series of moldings with smooth visible surfaces on both sides are made using the vacuum molding process, Fig. 56. Two mold halves are required. One half can... 

This polymer is suitable for long-term use at temperatures 0-130 C and can be easily reprocessed into articles by die casting. It also can be extruded and exposed to vacuum molding with deep drawing. 

In the CCC the filler is mixed with a resin, commonly phenolic resin, and sintered in a carbonization or graphitization step similar to the fabrication of synthetic graphite. The material obtained has a lower density, typically 20 0 % than synthetic graphite. The CCC allows the use of molding or vacuum molding processes. Lower plate thickness than synthetic graphite can be obtained. 

Vacuum molding techniques are used to create the embossments. With the embossments of the first and second opposed films being in register, one with the other, the surface layers of the film are brought into face-to-face contact under modest pressure, while at a temperature sufficient to provide a fusion or tacky state to create the bond (17). Basically, this technique goes back in the 1960 s (18),... 

A simple, portable and cheap apparatus was developed [64] for vacuum-molding reinforced plastic components and a prototype tape laying machine was also developed [64],... 

The matched molds will require special sealing for RTM and vacuum molding, as shown in Figure 21.49. The dynamic seal is the preferred construction. Resin is normally introduced at a central position of the mold cavity shape and can be introduced at the top or bottom of the mold, whichever is most convenient. 

A porous carbon fiber carbon composite with a density >0.2 gcm with a significant volume of mesopores (2 50 mn) and macropores (50-100 pm) which allow excellent fluid flow with minimal pressure drop has potential as catalyst support. Fortafll P200 PAN based carbon fiber was slurried in water with a phenolic resin, vacuum molded, dried at 50°C, cured for 3 h at 130°C and carbonized in a flow of N2 at 650°C. In this process, O2, CO2, H2O and CO were trapped inside the micropores during carbonization and gasified the surface of the PAN fibers, resulting in large surface areas (572 m g ) and mesopore volumes (1 cm g ), a possible candidate for a catalyst support [25 27). 

Vacuum molding n. This type of molding is used to mold fiberglass-reinforced plastics. The method allows molding without high temperatures and pressures. In this technique, layers of reinforced media are applied to the mold by hand. Resin is either sprayed or brushed on after each layer is positioned. The flexible sheet (usually cellophane or polyvinyl acetate) is placed over the lay up. Joints and seals are sealed and a vacuum causes the b to collapse over the face of the product not contacting the mold. The resultant pressure tends to eliminate voids and forces out any excess resin or entrapped air. Madox DM (1998) Handbook of physical vapor deposition (PVD) processing. Noyes Data Corporation, New York. 

AL-Tool/T-Lam, High-heat vacuum mold system, Seawolf Industries, Inc. 

The aluminum bore tube is made vacuum tight so that it can be used as part of the vacuum impregnation mold. (A vacuum tight mold is essential.) The outer shell of the vacuum mold consists of sheet steel, which is wrapped and clamped around the coil. The... 

Filament winding. Fiberglass strands or roving are wound in continuous lengths on a mandrel. Curing is at room temperature—in an oven or autoclave, or by bag or vacuum molding. 

Another approach is slurry molding and this technique was firstly used to manufacture carbon-carbon composites by Besmann et al. (2003). This process mixes phenolic resin with carbon fillers in water to create slurry which is fed out and vacuum molded into a preform. A second process called carbon chemical vapor infiltration (CVl) is then used to seal the plate for gas impermeability and for improvement of electrical conductivity. This process has been further developed by Huang et al. (2005) to reduce the cost caused by the CVl process and by Cunningham et al. (2007) to improve the properties of the bipolar plates. However, the mechanical properties of the bipolar plates were not found to be as high as the solely wet-lay-based plates (see Figures 6.7 and 6.8). 

Vacuum mold cavity Press can include a vacuum chamber around or within the mold providing removal of air and other gases from the cavity(s). 

Vacuum Molding n This type of molding is used to mold fiberglass-reinforced plastics. The method allows molding without high temperatures and pressures. In this technique, layers of reinforced media are applied to the mold by hand. Resin is either sprayed or brushed on... 

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