Tape materials

Possible tape materials include polyimide, polyester, polyethersulfone (PES), and polyparabanic acid (PPA) (18). Of these, polyimide is the most widely used material because its high melting point allows it to survive at temperatures up to 365°C. Although polyester is much cheaper than other materials, its use is limited to temperatures less than 160°C. PES and PPA, on the other hand, are half as cosdy as polyimide, and can survive maximum short-term temperatures of 220 and 275°C, respectively. PES has better dimensional stabiUty than polyimide, absorbs less moisture, and does not tear as easily however, it is inflammable and can be attacked by certain common solvents. Table 7 Hsts various plastic tapes and their properties. Common bump materials are gold, copper, and 95% Pb/5% Sn solder (see Tables 6 and 8 for properties see also References 2 and 21). 

Ceramic tape material Aluminum borosilicate and polymeric binders Number of micro channels 7... 

Figure 2 is a detail of the sloped wood cap used in Figure 1. Note that the joints are taped (at the top of the cant) and caulked (between the lead flooring and wood cant) to keep manufacturing components and product out of joints. The tape material is 3 inch wide, 2 ply, 100 percent cotton, grade B fabric with a warp and fill of approximately 78 x 78 x 72 pounds breaking strength. It should be adhesive-applied using a water insoluble nitrile rubber/ resin solution. These are commonly referred to as "Airplane Fabric" and "Pliobond 20" adhesive. The Fiberfrax Paper is used below lead flooring as an insulation barrier with a low thermal conductivity to resist heat required for installation of lead conductive floor. Note also that nonsparking nails are required. These are usually aluminum or brass.

Polyoxypropylene urethane polymer, mercaptan-terminated, 22 40-41 Polyparabanic acid (PPA) tape material, 17 836... 

Superabsorbents are superabsorbent polymers, which are loosely crosslinked hydrophilic polymers and have ionic charges in the polymers. They absorb water, swell, and retain aqueous solution above hundred times their own weight. Because of the excellent characteristics, the superabsorbents have been widely used in many applications such as disposable diapers, feminine napkins, soil additives in agricultural or horticultural applications, gel actuators, water-blocking tapes, materials for drug delivery system, absorbent pads, etc., where water absorbency or water retention is important. 

Distance between adjacent plies in lay-up of unidirectional tape materials. 

Oriented Film Film that has been oriented either monoaxially (in one direction), the direction of tear, or biaxially (in two directions), to achieve strength and stiffness. Monoaxially oriented tape exhibits stronger MD (machine direction) tensile properties than biaxially oriented tape. Materials that have been oriented bear an O before the acronym (e.g., OPS, oriented polystyrene). 

The first step in a filament winding process chain is the material rack. The fiber material, whether already impregnated, that is tape material, or not, that is, roving material, delivered on spools is mounted here. The number of spools depends on the winding head technology used and the components dimension. In addition to the material storage, a spool creel can also be... 

For processing fully consolidated tape materials the process simulation tool ProSimFRT has been developed at IVWProSimFRT enables simulation of the component quality depending on the void content and the surface roughness. The simulation can be used for tape winding as well as tape placement processes using a compaction roller. 

Whether coming already from the consolidated tape material or as a result of the impregnation process during winding, inhomogeneous distribution has to be avoided. Otherwise the resulting component will behave inhomo-geneously under mechanical load. 

Schledjewski, R. and Schlarb, A. K., In situ consolidation of thermoplastic tape material - Effects of tape quality on resulting part properties . Baltimore, Proceedings of Sampe 2007, USA, 2007. 

Khan, M. A., Mitschang, P. and Schledjewski, R., Tracing the void content development and identification of its effecting parameters during in situ consolidation of thermoplastic tape material . Polymers and Polymer Composites, 2010, 18(1), 1. 

As the pimch pierces the tape material, a roimd or square section of the tape is cut free and must be removed as a waste product of tire process. In many cases, the dies are hollow, as shown in Figure 6.11, and vacuum is applied to the base of the die to extract this unwanted material. Some high-end pimching systems also effectively float the tape to be punched on a... 

A die holder for a low volume CNC via punch system. This system is capable of simultaneously holding four via punches. Note the "slug" of cut tape material visible in the hollow center of... 

Amey, D.I. (DuPont Microcircuit Mater., Research Triangle Park, NC), Keating, M.Y., Smith, M.A., Horowitz, S.J., Donahue, P.C., Needes, C.R., Low loss tape materials system for 10 to 40 GHz application. Proceedings 2000 International Symposium on Microelectronics, SPIE Vol. 4339, 2000, pp. 654-658. 

The first method depends strongly on the tape thickness and the tape material used. Three to foin cuts are often necessary to open the first layer (Figure 9.41). Sometimes, the resistance values of a test circuit are shifted... 

Use a wet resin and dry fiber, if appropriate to the process. This method reduces the cost of filament winding. In Ref. 38, the cost for the large MX lannch canister wet filament wound by Hercules in the 1990-95 time period was 45.00/lb— less than the cost of just the prepreg tape material for many composite parts. 

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