Glass Fiber Orientation

The handbook features the relationships between the GRTP s and their properties—the relationships are displayed both in tabular form and graphically. The influence of composite variables—volume of glass fiber glass strand solids and bundle size glass filament diameter, length, and orientation—on properties are similarly displayed. 

Another unique feature of the handbook is the manner in which the polymers and their associated properties are presented. In one breakout, the GRTP s are displayed as the independent variable in a second breakout, the properties are displayed as the independent variable. 

The handbook was prepared by Ms. Joan B. Titus, Plastics Technical Evaluation Center (PLASTEC), the Defense Department s specialized information center on plastics, located at the US Army Armament Research and Development Command, Dover, NJ. 

The US Army DARCOM policy is to release Engineering Design Handbooks in accordance with DOD Directive 7230.7, 18 September 1973. Procedures for acquiring Handbooks follow  

Letterkenny Army Depot ATTN SDSLE-SAAD Chambersburg, PA 17201. 

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When the SMC PCBs to be placed in the compression mold are cut to size, whereby they cover 30-70 % of the mold surface depending on the desired flow processes, warpage of the later stmctural components can be influenced by way of glass fiber orientations. Calculation of the melt front is an important element in these considerations. 

Effect of Load Angle-Glass Fiber Orientation... 

Tensile values at given specimen locations and estimates of localized glass fiber orientation angles 0 are given for each composite material in Tables 12.10 and 12.11. Table 12.10 features characteristics of longitudinal flow in the V direction, whereas Table 12.11 provides analysis of transverse flow in the X direction. 

Improved processing techniques which reduce compound degradation and fiber attrition, and promote optimum glass fiber orientation. 

Glass fiber orientation results with lateral flow during molding. Resin/glass separation can occur if the material flows too far. 

Fig. 4.1 (1) ESEM images of rod like orientation of Unfilled LCPs at magnification scale (a) 1 mm, (b) 500 m, (c) cross sectional view of LCP pellets, (d) surface view of filler arrangement in pellet (Rahman 2013), (e) diameter of filler and (f) length of filler (2) ESEM images of glass fiber orientation at different shear rates (a) 0 s magnification scale 500 m, (b) 1 s scale 1 mm, (c) 10 s scale 200 m, (magnification scale 500) 100 s scale 1 mm (Rahman et al. 2013)...

M. Vincent, J.F. Agassant. Experimental study and calculations of short glass fiber orientation in a center gated molded disc. Polym. Compos., 1 (2), 76-83,... 

Glass filled nylon weld results are promising. IR samples burst at 3.10 MPa or 67% of parent material, which is slightly higher than vibration welded samples. The increased weld strength over VW may be linked to glass fiber orientation at the weld. 

Polarized light microscopy was used to collect photomicrographs from a number of cross-sectioned samples for microstructure evaluation and to determine glass fiber orientations. Some samples were also cold mounted and examined using microscopy. Comparisons were made for filled samples welded to filled samples, unfilled samples welded to unfilled samples, and filled samples welded to unfilled samples for both US-assisted hot plate welding and hot plate welding without US assist. 

Laser welded joints were examined nsing optical and polarized ligjit micioscopy, under both reflected and transmitted light, as well as scanning election microscopy. The following materials were used polycarbonate, polyamide-6, and polyamide-6 reinforeed with 30% glass fibers. The influence of laser power on the sh e, dimensions, and quality of laser-welded joints was evaluated, in both the absorbent and non-absorbent parts of the joint. Glass fiber orientation distributions were also examined. The effects of polymer type and fiber reinforcement, as well as laser power, on the dimensions and quality of the joints are reported. 

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