Long fiber reinforced

Thomason, J. L., Long fiber reinforced polypropylene composites, presentation given at the Gordon Conference on Composites, Ventura, CA, 10-15 January, 1997. 

Fig. 11.30 Effect of preheating 50% by weight E-glass fiber-filled polyamide pulltruded pellets on fiber lengths at the screw tip of a 300-ton 23.86-oz reciprocating injection molding machine. [Reprinted by permission from C. G. Gogos, C. K. Yoon, and J. Brizzolara, Injection Molding Process Development for Long Fiber Reinforced Thermoplastics, SPE ANTEC Tech. Papers, 40, 384 (1994).]...

C. G. Gogos, C. K. Yoon, and J. Brizzolara, Injection Molding Process Development for Long Fiber Reinforced Thermoplastics, SPE ANTEC Tech. Papers, 40, 384 (1994). 

These long-fiber-reinforced materials present mechanical properties that can be tailored by orientation of the fibers in the desired directions. The preparation and properties of these materials has been studied by several authors [11, 13-15]. 

The same test speeds as for the tensile test are permitted, although in practice these lend to be limited to the slowest end of the range. The speed closest to I % strain per min is specified, and this translates into 2mm/min for the preferred test piece. The latter is a bar of length 80 mm and cross section 10 x 4 mm this can be taken from the center of the multipurpose test specimen of ISO 3167 [25). When the preferred test piece cannot be obtained, other specimen sizes are permitted. The length of the test piece should be (20 1) times the thickness, and the width increases from 10 mm to 50 mm as the thickness varies from 3 to 50 mm. Below 3 mm thickness, a width of 25 mm is used. These figures apply to plastics other than textile or long-fiber reinforced plastics, for w hich wider samples are typically used at a given thickness. Chapter 18 deals with these more fully. 

The first all-around automobile application of composite leaf-springs was made in the Sherpa 200 series van and mini buses built by Freight Rover. These fiber-reinforced plastic (FRP) components for high stress, high-temperature uses were developed by GKN. ICl s Verton, a long-fiber reinforced thermoplastic is also suitable for such applications. 

IMMs with the proper screw designs process short or long fiber reinforced compounds. As an example with a suitable machine and... 

Long fiber reinforced compounds polyamides. Basic/mechanical/thermal properties ... 

Direct Long Fiber-Reinforced Thermoplastic Process (Overview)... 

In direct processing of long fiber-reinforced plastics, the material and the structural component are created, so-to-speak, during the production process itself. For this reason, processing has a significant influence on the properties of the resulting structural components. 

Interim storage of the fiber composite material is realized in a heat accumulator, from which it is discharged in cycles by a ram, chopped into molding compound units by a cutter at the end of the accumulator, and transported on a discharge belt. The plasticized material produced in this way is transferred into a compression mold, then formed into a structural component in an extrasion process. The finishing steps are the same as in other CM methods used for long fiber-reinforced thermoplastics. 

A fully plastic prototype made of long fiber-reinforced polypropylene (PP) GF 30 with locally integrated glass textile reinforcement in the belt area was developed about 1 year ago. The manufacturing technique used is hot pressing, developed in a vertical scheme involving many partners in a 3-year project funded by the Federal German Education and Research Ministry (BMBF). 

Table 1 compares their opportunities and risks. Fig. 1 shows the frontend plastic element in an LFT-D version (direct long fiber-reinforced thermoplastics). For detailed descriptions see [5, 11]). 

Table 1 Opportunities and risks involved in an automobile frontend made of long fiber-reinforced polypropylene with locally integrated glass textile inserts (LPT GF PP-D)...

Long fiber-reinforced thermoplastics are becoming increasingly important as materials, in the automotive sector in particular. The light construction aspect of... 

Trdster S, Geiger O, Henning F, Eyerer P (2004) Added value for long-fiber reinforced thermoplastic components by in-line-compounding in the LFT-D-ILC process. SPE Paper 1121, ANTEC 2004, Chicago, IL... 

Thermoplastics - long fiber-reinforced, textile-reinforced, woven mat-rein-forced or with local hybrid fiber reinforcement - will gain ground in the direction of large-scale production series and structural parts production. 

D.M. Bigg, Manufacturing methods for long fiber reinforced polypropylene sheets and laminates, ed. by J. KaigCT-Kocsis, in Polypropylene Structure, Blends and Composites. voL 3 (Chapman Hall, London, 1995), pp. 263-292... 

Important distinguishing properties of the composite materials are the shape of the reinforcement phase, such as long fibers, short fibers, and particle. Concerning the mechanical properties, the best results are achieved by long-fiber reinforcements. Since they are not economically feasible because of their complex manufacturing process, it is preferred to use short-fiber or particle reinforcements. They do not have the same resistance as the long-fiber reinforcement, but the potential gain of stiffness, resistance to wear, and other property improvement are usually sufficient and acceptable. 

---