Effect of CaCO3 Content in Resin Transfer Molding Process

2013 ◽  
Vol 334-335 ◽  
pp. 188-192 ◽  
Author(s):  
Iran Rodrigues de Oliveira ◽  
Sandro Campos Amico ◽  
F. Ferreira Luz ◽  
R. Barcella ◽  
V.M. França Bezerra ◽  
...  
Keyword(s):  
Porous Media ◽  
Low Cost ◽  
Resin Transfer Molding ◽  
Molding Process ◽  
Transfer Molding ◽  
Advanced Composite ◽  
Rtm Process ◽  
Advanced Composite Materials ◽  
Closed Mold ◽  
The Individual

Composite material can be defined as a combination of two or more materials on a macroscale to form a useful material, often showing properties that none of the individual independent components shows. Resin Transfer Molding (RTM) is one of the most widely known composite manufacturing technique of the liquid molding family, being extensively studied and used to obtain advanced composite materials comprised of fibers embedded in a thermoset polymer matrix. This technique consists in injecting a resin pre-catalysed thermosetting in a closed mold containing a dry fiber preform, where the resin is impregnated. The aim of this study is to investigate the effect caused by the use of CaCO3filled resin on the characteristics of the RTM process. Several experiments were conducted using glass fiber mat and polyester resin molded in a RTM system with cavity dimensions of 320 x 150 x 3.6 mm, at room temperature, and different CaCO3content (0, 10, 20, 30 and 40% in weight). The results show that the use of filled resin with CaCO3influences the resin viscosity and the porous media permeability, making it difficult to fill the porous media during the molding process, however it is possible to make composite with a good quality and low cost.

Application of Calcium Carbonate in Resin Transfer Molding Process

2014 ◽  
Vol 353 ◽  
pp. 39-43 ◽  
Author(s):  
Iran Rodrigues de Oliveira ◽  
Sandro Campos Amico ◽  
R. Barcella ◽  
Antônio Gilson Barbosa de Lima
Keyword(s):  
Calcium Carbonate ◽  
Low Cost ◽  
Resin Transfer Molding ◽  
Injection Pressure ◽  
Molding Process ◽  
Transfer Molding ◽  
Industrial Sectors ◽  
Advanced Composite Materials ◽  
Filling Time ◽  
Manufacturing Techniques

Resin Transfer Molding (RTM) is one of the most widely known composite manufacturing techniques of the liquid molding family, being extensively studied and used to obtain advanced composite materials comprised of fibers embedded in a thermoset polymer matrix. Nowadays, RTM is used by many industrial sectors such as automotive, aerospace, civil and sporting equipment. Therefore, the objective of this study is to verify the effect of calcium carbonate mixed in resin in the RTM process. Several rectilinear infiltration experiments were conducted using glass fiber mat molded in a RTM system with cavity dimensions of 320 x 150 x 3.6 mm, room temperature, maximum injection pressure 0.202 bar and different content of CaCO3 (10 and 40%) with particle size of 75μm. The results show that the use of filled resin with CaCO3 influences the preform impregnation during the RTM molding, changing the filling time and flow from position, however it is possible to make the composite with a good quality and low cost.

Uncertainty Modeling of Residual Stress Development in Polymeric Composites Manufactured With Resin Transfer Molding Process

2007 ◽  
Author(s):  
Kuang-Ting Hsiao
Keyword(s):  
Residual Stress ◽  
Resin Transfer Molding ◽  
Parametric Uncertainty ◽  
Polymeric Composite ◽  
Cure Kinetics ◽  
Polymeric Composites ◽  
Molding Process ◽  
Stress Development ◽  
Transfer Molding ◽  
Rtm Process

Resin Transfer Molding (RTM) is an advanced process to manufacture high quality thermoset polymeric composites. The quality of the composite depends on the resin infusion stage and the cure stage during the RTM process. The resin curing is a complex exothermic process which involves resin mechanical property evolution, resin volume shrinkage, thermal expansion, heat transfer, and chemical reaction. Since the fibers and resin have many differences in their physical properties, the composite cure stage inevitably introduces the undesired residual stress to the composite parts. As the residual stress could sometimes generate local matrix failure or degrade the performance of the composite, it is important to model and minimize the residual stress. This paper presents a model to predict the residual stress development during the composite cure process. By slightly disturbing the manufacturing parameters such as the mold heating cycle and the cure kinetics of polymer, the variations of residual stress development during the RTM process can be modeled and compared. A parametric uncertainty study of the residual stress development in the polymeric composite manufactured with RTM will be performed and discussed.

Preparation and Properties of a Novel Water Soluble Core Material for the Resin Transfer Molding Process

2011 ◽  
Vol 306-307 ◽  
pp. 844-847
Author(s):  
Quan Zhou Li ◽  
Xiao Qing Wu
Keyword(s):  
Compressive Strength ◽  
Resin Transfer Molding ◽  
Water Soluble ◽  
Core Material ◽  
Molding Process ◽  
Transfer Molding ◽  
The Core ◽  
Rtm Process ◽  
Binder Solution ◽  
Core Materials

A novel water soluble core material composed of alumina, quartz sand, kaolin, gypsum powder and the solution of binders was prepared. The influence of different mass concentration of Polyethylene Glycol (PEG) binder solution and sodium silicate compounded (SS) binders solution on water soluble performance and compressive strength of the core materials was investigated, respectively. The results show that the compressive strength and solubility rate of the core materials, with the concentration of 30% of SS binders solution, are 1.023MPa and 0.24g/s respectively, which is satisfied for the requirements of Resin Transfer Molding (RTM) process completely.

Fabrication of T-Shaped Structural Composite through Resin Transfer Molding

1995 ◽  
Vol 29 (16) ◽  
pp. 2192-2214 ◽  
Author(s):  
Wen-Bin Young ◽  
Min-Te Chuang
Keyword(s):  
Low Cost ◽  
Resin Transfer Molding ◽  
Mold Filling ◽  
Transfer Molding ◽  
Rtm Process ◽  
Resin Impregnation ◽  
Composite Fabrication ◽  
Fiber Reinforcements ◽  
Fiber Materials ◽  
Dry Spot

Resin transfer molding (RTM) combines resin impregnation and composite fabrication in one process. It simplifies the process for composite fabrication and has the advantages of automation, low cost, and versatile design of fiber reinforcements. The RTM process was used in this study to fabricate T-shaped stuctural composites. Edge effects due to the gap between the fiber mats and the mold or the imperfect sealing of the matting mold resulted in edge channeling flows, leading to dry spot enclosure in the composite. It was found that a vacuum in the mold cavity could reduce the size of the dry spot. Proper control or prevention of the edge flows will reduce the possibility of dry spot formation. Numerical simulations of the mold filling were conducted to study the effect of gate locations on the mold filling patterns and edge channeling flows. Mechanical pulling tests were conducted to investigate the joint strengths of the T-shaped structure for different fiber materials. Fiber stitching on the rib provided an improvement in the joint strength while different fiber materials without fiber stitching tended to have the same joint strengths.

Effects of Weirs on the Resin Transfer Molding Process

2001 ◽  
Author(s):  
Kiran M. D’Silva ◽  
Su-Seng Pang ◽  
Kurt C. Schulz
Keyword(s):  
Glass Fibers ◽  
Resin Transfer Molding ◽  
Mold Filling ◽  
Laminated Plates ◽  
Molding Process ◽  
Outlet Port ◽  
Transfer Molding ◽  
Inlet Port ◽  
Rtm Process ◽  
Filling Time

Abstract Low mold filling time and improper fiber wetting are the main problems faced by the manufacturers applying the Resin Transfer Molding (RTM) process. The objective of this work was to minimize these problems and to study the effect of weirs on the RTM process. A mold was designed such that the lower mold plate contains two weirs, one at the resin inlet port and the other at the outlet port. The purpose of adding the weirs is to provide a continuous inlet stream near the resin inlet port and to cause backpressure near the outlet port to induce complete mold filling. Laminated plates were prepared using glass fibers and epoxy resin (combination of EPON resin-862 and curing agent W). The test parameters investigated, such as void contents, dry spots and mold filling time, were compared with those of samples that were prepared without the use of weirs. It was found that the presence of weirs resulted in significant elimination of dry spots, minimization of void contents and a reduction in mold filling time. As a result, the cost required to manufacture composite parts can be reduced by the use of weirs. In addition to the experimental investigation, a computer simulation (using LCMFLOT software) of resin flow inside the mold cavity was conducted. Many simulations were run in order to optimize the height and shape of the weir. Rectangular weirs of height 2.54 mm showed minimum mold fill time. It was found that the results obtained from the experimental work and flow simulations are in good agreement. Based on this work, it is evident that complex parts can be produced in less cycle time if weirs are positioned at appropriate locations.

scholarly journals Embedded Based Real-Time Monitoring in the High-Pressure Resin Transfer Molding Process for CFRP

2019 ◽  
Vol 9 (9) ◽  
pp. 1795 ◽  
Author(s):  
Kim ◽  
Kim ◽  
Hwang ◽  
Kim
Keyword(s):  
High Pressure ◽  
Real Time ◽  
Process Monitoring ◽  
High Speed ◽  
Resin Transfer Molding ◽  
Time Signal ◽  
Process Variables ◽  
Molding Process ◽  
Transfer Molding ◽  
Rtm Process

Carbon Fiber Reinforced Plastics (CFRP) is a material developed for its high strength and light weight in a broad variety of industries including aerospace, automotive, and leisure. Due to the rapid molding cycle time, high-pressure resin transfer molding (HP-RTM) processes are prone to molding defects and susceptible to various process variables such as the resin injection rate, pressure and temperature in the mold, vacuum, end-gap, pressing force, and binder. In recent years, process monitoring technology with various sensors has been applied to stabilize the HP-RTM process and control process variables. The field-programmable gate array (FPGA) based embedded monitoring system proposed in this study enabled high-speed real-time signal processing with multiple sensors, namely pressure, temperature, and linear variable differential transformer (LVDT), and proved feasibility in the field. In the HP-RTM process, the impregnation and curing of the resin were predicted from the cavity pressure and temperature variations during the injection and curing stages. In addition, the thickness of the CFRP specimen was deduced from the change in the end-gap through the detection of the LVDT signal. Therefore, the causes of molding defects were analyzed through process monitoring and the influence of molding defects on the molding quality of CFRP was investigated.

On Computer Aided Formation Framework for Composite Material

2013 ◽  
Vol 710 ◽  
pp. 775-778
Author(s):  
Juan Wang ◽  
Si Yu Lai
Keyword(s):  
Process Integration ◽  
Resin Transfer Molding ◽  
Object Oriented Programming ◽  
System Structure ◽  
Planning System ◽  
Computer Assisted ◽  
Molding Process ◽  
Transfer Molding ◽  
Component Technique ◽  
Rtm Process

The composite molding process design systems are developed on specific manufacturing resources or specific environment whenever at home and abroad, which enjoys a poor versatility. We built the system structure and flow for composite process integration framework after the computer-assisted resin transfer molding software has been developed. Then, studied the template-based data structure and established the model that can form a CAPP application system rapidly; developed a three levels similar cases retrieval structure based on part level, shape level and feature level; realized the customization of process card by adopting the excel template method. Finally, a resin transfer molding (RTM) process planning system is customized by object oriented programming (OOP) and component technique to verity the validity and feasibility of the integrating framework.

Study on Compression Transfer Molding

1995 ◽  
Vol 29 (16) ◽  
pp. 2180-2191 ◽  
Author(s):  
Wen-Bin Young ◽  
Cheng-Wey Chiu
Keyword(s):  
Low Cost ◽  
Fiber Reinforcement ◽  
Mold Filling ◽  
Thickness Direction ◽  
Molding Process ◽  
Transfer Molding ◽  
Rtm Process ◽  
Resin Impregnation ◽  
Filling Time ◽  
Part Dimension

Resin transfer molding (RTM) finishes the resin impregnation and composite fabrication at the same time. It simplifies the process for composites fabrication and has the advantages of automation, low cost, and versatile design of fiber reinforcement. Therefore, the RTM process is widely used in the architecture, automotive, and aerospace industries. However, in the RTM process, resin must flow through the fiber reinforcement in the planar direction, which, in some cases such as fabrications of large panels, may need a long time for the mold filling. If the part dimension is too large or the fiber permeability is too low, the mold filling process may not be able to complete before the resin gels. Therefore, some modification for the RTM process is necessary in order to reduce the mold filling time. In the compression transfer molding, the mold opens a small gap for the resin to fill in between fiber mats and the mold, and then compresses the fiber reinforcement to be impregnated by the resin in the thickness direction. In this way, since resin is forced into the fiber reinforcements in the thickness direction, the damage of the fibers will be minimized. In addition, the mold filling time will be reduced due to the different flow path of the resin inside the mold. This study explored the possibility of using the compression transfer molding process and also identified the key parameters regarding the process.

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