RP properties

An important type of orienting fabricated products concerns applying directional properties to plastics by using fiber reinforcements. Orientation is the alignment of fiber reinforcement within the product that affects mechanical properties. The reinforced plastic (RP) properties increase in the direction of alignment (Figure 3.4). 

Different types of reinforcement construction are used to meet different RP properties and/or simplify reinforcement layup fabricating processes to meet design performance shape requirements. They include woven, nonwoven, rovings, preforms, and others. These different constructions are used to provide different processing and directional properties. 

Long-fiber nylon 11 and 12 (30/50 wt% glass fiber) shows up to 200% improvement in impact, dimensional stability, good surface appearance, low moisture content and improved abrasion resistance. Table 2.4 provides short- and long-glass fiber/nylon 6/6 RPs properties at elevated temperatures. 

Table 2.4 Example of short- and long-glass fiber/nylon 6/6 RPs properties at elevated temperatures...

Table 3,16 Comparing RP properties of TS polyester with different forms of glass fibers...

Figure 7.11 Examples of RP properties based on fiber lay-up directional patterns ...

Computer programs developed since the 1980s continually improve and have made it possible to aid in modeling the complex interactions of the many processing fectors that include RP properties and behaviors, geometry of the part, tool making quality applied to manufacture of dies or molds, and very important the processing conditions and fluctuations inherent in the equipment and materials. 

The use of computer software RP programs in design, RP property data, processing fabrication, troubleshooting, and related fields is widespread. It is increasingly important to keep up to date continually with the nature and prospects of new software technologies. 

Anisotropic construction RP properties are different in different directions along the laminate flat plane. 

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