Restraint of Voids Generated Inside Injection Molded Products by In-Mold Pressing Method

2018 ◽  
Vol 12 (6) ◽  
pp. 930-939 ◽  
Author(s):  
Atsushi Motegi ◽  
Tomohiro Hishida ◽  
Yasuhiko Murata ◽  
◽  
Keyword(s):  
Injection Molding ◽  
High Strength ◽  
Compression Molding ◽  
Fiber Reinforced ◽  
Pressing Method ◽  
Glass Fiber Reinforced Plastic ◽  
Fiber Reinforced Plastic ◽  
Reinforced Plastic ◽  
Injection Molded ◽  
Injection Compression Molding

In recent years, long glass fiber reinforced plastic and carbon fiber reinforced plastic have begun to be used for structural components that require high strength. As a result, thick-walled injection molded products are being manufactured. However, defects, known as voids, are generated inside the molded product and decrease the strength of the molded product, posing a significant problem at molding production sites. The partial compression method, which is a type of injection compression molding, is effective in preventing voids in thick-walled injection molding. However, there have been limited studies that comprehensively investigated the effects of the compression conditions on void prevention in thick-walled injection molding products or the shape and dimension of the molded product, or the issues in the molded product produced by applying compression. The authors have previously proposed the in-mold pressing (IMP) method, which allows the application of partial compression without the use of an injection compression molding machine and verified its validity. In this study, we proposed a compression device in which a servomotor-driven hydraulic pump actuator is used to propel a movable rod to apply compression to the melt inside the mold cavity. The IMP method using this device was applied to mold thick-walled products with thicknesses of 10 mm and greater, and the effects of compression on the generation of voids inside the molded product and the shape and dimensions of the product were investigated. The results indicate that the generation of voids can be prevented by application of this method. In addition, it was found that marginal deformations, which can pose issues, occur in the molded product when compressive stresses generated inside the molded product by compression are released after demolding.

Experimental Research on Interlaminal Shear Strength of GFRP Bridge Decks under Simulated Concrete Environment

2012 ◽  
Vol 525-526 ◽  
pp. 249-252
Author(s):  
Wei Chen Xue ◽  
Kai Fu
Keyword(s):  
Shear Strength ◽  
Bridge Deck ◽  
Bridge Decks ◽  
High Strength ◽  
Sample Surface ◽  
Fiber Reinforced ◽  
Glass Fiber Reinforced Plastic ◽  
Fiber Reinforced Plastic ◽  
Reinforced Plastic ◽  
Shear Strength Degradation

Fiber reinforced plastic (FRP) composite which has high strength, high fatigue resistance, low density, and better corrosion resistances is desirable characteristics for bridge applications, especially decks. According to the ACI 440.3R04, Glass fiber reinforced plastic (GFRP) bridge deck samples were immersed into the simulated concrete environment at 60 for 92d (corresponds to the natural environment 25 years). The results show that, with the time increased, the interlaminal shear strength of GFRP bridge decks decreased significantly. After being exposed to the simulated concrete environment for 3.65d, 18d, 36.5d and 92d, the interlaminal shear strength degradation of GFRP bridge decks were 18.69%, 25.90%, 50.93% and 53.74%, respectively. The micro-formation of the GFRP bridge deck sample surface was surveyed under scanning electron microscopy (SEM), which indicated that with the aging time increased, corrosion pits in the surface of GFRP bridge decks became more obviously and the interface between fiber and resin was severely damaged. Therefore, the degradation of FRP under the simulated concrete environment should be considered in the design of FRP bridge decks.

Fabrication and Testing of FRP Open Coil Springs

2014 ◽  
Vol 592-594 ◽  
pp. 1065-1069 ◽  
Author(s):  
R. Arularasan ◽  
Y.K. Sabapathy
Keyword(s):  
Automobile Industry ◽  
Weight Ratio ◽  
High Strength ◽  
Fiber Reinforced ◽  
Variable Parameters ◽  
Glass Fiber Reinforced Plastic ◽  
Fiber Reinforced Plastic ◽  
Glass Fiber Reinforced ◽  
Reinforced Plastic ◽  
Low Weight

Increasing competition and innovation in automobile sector tends to modify the existing products or replace old products by new and advanced material products. A suspension system of vehicle is also an area where these innovations are carried out regularly. Now days the automobile Industry has shown much interest in using Fiber Reinforced Plastic (FRP) components replacing conventional steel components due to its “high strength to low weight” ratio. Therefore replacement the steel open coil suspension springs (in heavy automobiles) with Glass Fiber Reinforced Plastic (GFRP) open coil springs with the main aim to reduce its weight and thereby reduce the fuel consumption to some extent. A semi mechanized pultrusion process (E –Glass and Epoxy Resin) and braiding process is selected for fabricating the GFRP open coil springs. It is then tested in lab to study some of the variable parameters. Keywords: Fiber reinforced plastic (FRP) , Coil spring , Pultrusion

scholarly journals Research and Design of Submerged Vehicle’s Propeller Blade

2019 ◽  
Vol 8 (12S) ◽  
pp. 324-329
Keyword(s):  
High Strength ◽  
Fiber Reinforced ◽  
Propeller Blade ◽  
Glass Fiber Reinforced Plastic ◽  
Fiber Reinforced Plastic ◽  
Glass Fiber Reinforced ◽  
Reinforced Plastic ◽  
Ansys Apdl ◽  
Von Mises ◽  
Research And Design

Recently, Fiber Reinforced Composite is used for making a propeller blade to develop its performance by increasing the payload and underwater speed of the vehicle. As a consequence of its feathery weight & high strength, numerous scholars/scientist substituted the conventional metallic material with composite material for crafting the propeller. In the contemporaneous work, predictions of pressure circulation around the profile of a propeller blade as a result of hydrostatic pressure difference are existing. Static structural stress investigation was executed for a single combination i.e. carbon fiber reinforced plastic (CFRP) & for hybrid condensation (a combination of two composite materials) i.e. CFRP & Glass Fiber Reinforced Plastic (GFRP). ANSYS APDL software is used to conclude von Mises pressure developed in the propeller blade. The result has been given away that it is more beneficial to use the hybrid blended material than the composite one. The weight value of propeller blade is found to be lower for the hybrid complexes, proposing the intrinsic worth of the contemporaneous work.

The Importance of Material Structure in the Laser Cutting of Glass Fiber Reinforced Plastic Composites

1995 ◽  
Vol 117 (1) ◽  
pp. 133-138 ◽  
Author(s):  
G. Caprino ◽  
V. Tagliaferri ◽  
L. Covelli
Keyword(s):  
Experimental Data ◽  
Glass Fiber ◽  
Laser Cutting ◽  
Material Structure ◽  
Fiber Reinforced ◽  
Fiber Volume ◽  
Glass Fiber Reinforced Plastic ◽  
Fiber Reinforced Plastic ◽  
Glass Fiber Reinforced ◽  
Reinforced Plastic

A previously proposed micromechanical formula, aiming to predict the vaporization energy Qv of composite materials as a function of fiber and matrix properties and fiber volume ratio, was assessed. The experimental data, obtained on glass fiber reinforced plastic panels with different fiber contents cut by a medium power CO2 cw laser, were treated according to a procedure previously suggested, in order to evaluate Qv. An excellent agreement was found between experimental and theoretical Qv values. Theory was then used to predict the response to laser cutting of a composite material with a fiber content varying along the thickness. The theoretical predictions indicated that, in this case, the interpretation of the experimental results may be misleading, bringing to errors in the evaluation of the material thermal properties, or in the prediction of the kerf depth. Some experimental data were obtained, confirming the theoretical findings.

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