Thursday, December 31, 2009

Dyneema in Composite Armor

Dyneema is an ultra high molecular weight polyethylene fiber manufactured by Dutch company DSM Dyneema. The properties of Dyneema, which include high tensile strength, allow it to be one of the best performing reinforcements used in composite armor. Composite armor manufactured with Dyneema is often lighter-weight then other material options; which is why Dyneema is used on military vehicles across the globe.

Here is an interesting interview with Ivo Oerlemans, Marketing Manager Vehicle Protection at DSM Dyneema from It worth the read if you are following the composite armor industry.

Photo Credit ob1left via flicker

Wednesday, December 30, 2009

Carbon Fiber Roller Skates

Prototype trials in China, Australia & Singapore from Chariot Skates on Vimeo.

On this blog I like to point out new an interesting uses of composite materials. Well, here is a new type of roller skate using carbon fiber. Very interesting, the larger wheels allow it to go over rougher terrain that standard inline skates would have problems with.

Thursday, December 10, 2009

Composite Material vs Metal

Perhaps the first driving factor for replacing metal components with composite materials was the resistance fiber reinforced polymers have to corrosion. The marine industry began to embrace composite materials shortly after WWII, manufacturing boats impervious to the corrosive salt environment.

Today, modern metal alloys such as aluminum, titanium, and even stainless steel are used in industries, such as aerospace, where corrosion in unacceptable. Although these metals are not "prone" to corrosion, there is still the risk of galvanic corrosion, which occurs when two dissimilar metals are in contact with one another.

In fact, due to the conductive properties of carbon fiber reinforced composites, there is a growing concern in cases where metal components are interacting with carbon fiber components. This is perhaps a major issue on designing the new generation of Boeing and Airbus airframes.

Corrosion will continue to be an issue for metal products, and corrosion will continue to be a driving factor for the integration of composite materials. For a good illustration of this, here is an interesting blog post discussing how the household cleaner Simple Green can corrode aluminum.

Photo Credit: Nomads: will create via flicker

Wednesday, December 9, 2009

Advanced Thermal Composite Materials

Here is an interesting technical presentation on advanced thermal materials.

Tuesday, December 8, 2009

Composite Waste water Pipes

Photo Credit: Roantrum via flicker

Composite waste water pipes are becoming increasingly popular as traditional steel and concrete pipes are due for replacement around the world. Concrete, being a porous material allows moisture to penetrate and corrode the steel reinforcement. This can damage the structural integrity of the pipes, and ultimately will require retrofitting.

Here is an article from WaterWorld on the increasing use of FRP composites in waste water pump stations, the article states:
"Many companies in the wastewater treatment industry make their products out of steel and concrete. But steel is highly susceptible to corrosion caused by various chemicals in the wastewater stream. This tendency for corrosion is often accelerated by chloride-rich environments, such as areas with natural salt water concentrations – ultimately shortening the life spans of these lift stations Concrete stations tend to crack as they settle, resulting in leakage and typically higher maintenance costs. Both steel and concrete stations also are extremely heavy, making them difficult to transport and install."

Friday, December 4, 2009

Competition for Better Composites

Throughout time, competitions have led way to some of the greatest innovations. Like the recent x-prize and now the automotive x-prize, there comes a new UK based competition.

In search for better processing of composite materials, a competition is being held where the winner will receive 5 million British pounds. More info: Reinforced Plastics

Photo Credit: Eric Charlton via flicker

Thursday, December 3, 2009

Composite Shipping Container

Since the advent of composite materials, and in particular, strong lightweight composite sandwich panels, engineers have been trying to replace the commonly used steel sea-land ISO shipping containers with composite materials.

It seems logical, steel shipping containers are extremely heavy, they spend a good deal of their life in a highly corrosive environment, and they don't last very long. However, the main barrier to entry is the fact that steel cargo containers are dirt cheap, especially as the majority of these containers are manufactured in low labor Asian markets.

As the raw material costs of steel rise, composite materials will have more of a realistic chance. In particular, niche composite containers such as refrigerated containers will likely be the first to be introduced.

Here is an article discussing a development program through the Department of Homeland Security for the design of composite tamper-proof containers. Besides the need for containers to be tamper proof for homeland security reasons, containers that are x-ray transparent will be easier to inspect at ports. Composite material is the viable long-term solution.

It is likely the use of composite shipping containers is inevitable. One aspect that must be kept in the forefront during the design process, is the containers' end of life. Current steel containers are easily recyclable, and the same will need to be true of composite replacements. Perhaps reinforced thermoplastic composites will be the design winner...

Photo Credit: Marc oh! via flicker

Wednesday, December 2, 2009

What are Composite Materials?

Here is an interesting introduction to composite materials from a more technical point of view.
Introduction To Composite Materials C Zweben
View more documents from chzweben.