06

Feb

Composite Fabrication Methods

There are numerous methods for fabricating composite components. Some methods have been borrowed (injection molding from the plastic industry, for example), but many were developed to meet specific design or manufacturing challenges faced with fiber-reinforced polymers.

Carbon Fiber and other Composite fabrication processes typically involve some form of molding, to shape the resin and reinforcement. A mold tool is required to give the unformed resin/fiber combination its shape prior to and during cure.

 

Choice of fabrics

Choosing a fabric type is mostly dependant on two factors – weave type and thickness.  Determining the weave type is based upon your aesthetic and conformability requirements.  The most common fabric chosen for aesthetic applications is typically a 3K 2×2 twill for carbon fabric applications.  This fabric provides the most elegant look of all weave types.  One of the most flexible fabrics is generally a twill weave (note that a 4×4 twill will be more flexible than a 2×2).  The least conforming fabric is a plain weave.

 

What thickness you need in a particular fabric is dependent on your application.  For cosmetic purposes using carbon fiber fabric, a 3K carbon is often an ideal choice.  For structural applications, the most cost effective solution is to use the thickest possible fabric.  Thicker fabrics are cheaper per sqm than multiple layers of thinner fabrics, although thinner fabrics will generally conform better to complex curves than thicker fabrics.

 

 

The Overlay Method

The overlay method is the simplest of all the laminating methods.  Generally it involves finding an existing piece and sanding it lightly, then carbon fiber or other composite fabric is laid over the top of this existing piece, and resin is applied.  Finishing such a piece using the overlay method generally involves one of two techniques.  The first is sanding and/or buffing the finished overlay composite piece to a shine.  The second option is to sand the piece smooth, then apply a final coat of resin or add a clear coat, typically of urethane for epoxy, or a polyester clear coat for a polyester based resin.The overlay method is commonly used when one custom piece needs to be made, or a small number of custom pieces need to be made.  The main disadvantage of using the overlay technique is that results can be inconsistent and one often needs to be at least somewhat “crafty” in order to be able to create professional looking pieces.

You can choose one of our laminating carbon fiber kits here  

 

Vacuum Bagging

Vacuum bagging is by far the most complex and expensive of all the methods, but usually results in the best final product.  The first step in vacuum bagging is to create a perfectly designed reverse mold of the final piece which you intend to make.  This mold can be made out of virtually any material, anything from silicon rubber molds to composite.  The second step involves laying your carbon fiber or other composite fabric(s) into your newly created mold, then applying either a release fabric for fairly flat products or a peel-ply for complex and curvy applications.  A release fabric is typically a plain weave nylon treated fabric that allow resin to pass through it, but the release fabric itself will not stick to the composite product.  A peel-ply is a stretchable rubber like membrane with small holes space throughout the membrane, allowing resin to be sucked through those holes.  Behind the peel-ply or release fabric you place a breather fabric.  The purpose of the breather fabric is to absorb the excess epoxy being pulled through the release fabric or peel-ply.  Behind the breather fabric is the vacuum bag itself.  This acts as a permanent barrier and helps create an airtight chamber so that the resin can be sucked away from the product.  Sealing the bag to the mold requires a special sticky tape.  This tape provide an airtight seal between the mold and the vacuum bag itself.  This tape is commonly referred to as sealant tape.

 

If producing large numbers of identical units, such as if you intend to go into production making one specific piece or product, vacuum bagging is an ideal method.  The disadvantages of using a vacuum bagging method are that it often requires a great deal of effort to create a perfect mold; it also often requires adjusting of the vacuum bag line(s) and possibly adjusting the individual suction of each line.  Because of this, it is common to go through at least three to five pieces until you perfect your product and are ready to go into production.  Therefore this method is generally not recommended if your intention is to create only a few specific pieces.

 

20

Jul

Carbon Fiber Fins

Enter The Future Of Lightweight Diving With Carbon Fiber Fins

Carbon fiber fins are not exactly new but until now they’ve mostly been limited to freediving fin styles. But in November 2017 at DEMA Submatix US was showing off one of the first ‘normal’ SCUBA diving fins made from carbon fiber we’ve seen to date.

The idea of using carbon fiber to build dive fins might seem gimmicky at first, but there’s some a great reason that most carbon fiber fins have been developed for freediving. Carbon fiber is legendary for its strength and power return so it was only a matter of time until we saw this futuristic material applied to dive fins for general SCUBA diving.

 

Not only are these fins incredibly light, they are great at transferring power from your leg kick to the water. Each Submatix fin weighs in at nearly half the weight of typical fins tipping the scales at just over 450 grams each, and a reasonable 24 inches or 60 centimeters long.

Of course carbon fiber isn’t cheap so you’re looking at a price of around $399 per pair for the privilege. While the price may be hefty, when you hold them in your hands you realize how much weight you can shave from your dive bag with a pair of these carbon fiber dive fins, and the reduced weight underwater doesn’t hurt either. (Submatix)

29

Nov

Recycled carbon fiber moves into automotive

Chery New Energy Automobile Technology Co. Ltd. in China has pledged to apply recycled carbon fiber from ELG Carbon Fibre to its eQ1 electric vehicle. The ultimate goal is to expand the fiber into higher volume vehicles.

 

ELG Carbon Fibre Ltd. (Coseley, UK) and Adesso Advanced Materials Wuhu Co. Ltd. (Wuhu, China) have concluded a MOU regarding cooperation to develop lightweight composite components for the automotive industry based on ELG’s recycled carbon fiber materials.

 

 

The initial focus of the cooperation is to investigate applications that have been identified by Chery New Energy Automobile Technology Co. Ltd. (Wuhu, China) on the Chery eQ1 electric vehicle. The goal is to further reduce the weight of the eQ1, which already makes extensive use of aluminium technology, through selective use of carbon fiber composites. The longer term intent is to then apply the knowledge gained from these projects in Chery’s conventional vehicles.

Following a preliminary evaluation of ELG’s materials by Professor Fan Guanghong’s team at the Advanced Manufacture Technology Center of China Academy of Machinery Science Technology (CAMTC), Chery has suggested initial applications to be investigated, and providing that technical and commercial targets are achieved.  ELG, Adesso and Chery intend to enter into a definite agreement to start full-scale production of these parts in Wuhu. This agreement would see ELG Carbon Fibre establish a carbon fiber recycling operation in China when sufficient volumes of recycled carbon fiber materials are required.

Frazer Barnes, managing director of ELG Carbon Fibre, says, “The eQ1, through its extensive use of aluminium, already represents a huge advancement in lightweighting for the Chinese car industry. We are pleased to be working with the innovative engineering team at Adesso and Chery to help them take the next step forward and start introducing carbon fibre composites into their vehicles”.

Dr. Bo Liang, president, chairman and CEO of Adesso, says, “Working together in this project enables us to address the barriers preventing large-scale use of carbon fiber composites in automotive applications —namely cost — through the use of recycled materials, design and manufacturing and collaboration with experienced partners. Our vision is that cooperation leads to an automotive composites hub in Wuhu. It also strengthens our vision on sustainability of the composite industry in China.”

Gao Lixin, deputy general manager of Chery Automobile Co. Ltd. and general manager of Chery New Energy Automobile Technology Co. Ltd., says, “There is a strong need to reduce the weight of both new energy and conventional vehicles in order to meet environmental and performance targets. We believe carbon fiber composites have an important role to play in this and through our cooperation with ELG and Adesso on the eQ1 project we will gain a significant learning curve advantage that we can then use in our conventional vehicles.”

 

Buy carbon fiber, fiberglass and other composites online in Australia at Beyond Materials

17

Nov

First Polish Road Bridge Made Using FRP Composites

The video documents the construction and testing of the longest single-span FRP composite bridge of its kind in the world. Made by Polish company Mostostal Warszawa in 2015 the bridge was part of the Com-bridge research project, co-financed by the National Centre of Research and Development’s program supporting scientific research and development activities on demonstration scale.

Buy carbon fiber, fiberglass and other composites online in Australia at Beyond Materials