The Superstrata brand features a fully unibody carbon fiber/polyamide frame manufactured using Arevo’s direct energy deposition (DED) additive manufacturing process. Photo Credit: Arevo
The sporting goods market was a boon to the advanced composites market in the final decade of the 20th century. Carbon fiber fishing rods were introduced with great fanfare — and sales. Golf club shafts and tennis rackets weren’t to be left out, and driven by the growing popularity of cycling races like the Tour de France, carbon fiber bicycles went from pro racing to bike trail and street, and saw numerous innovations in the 1990s and 2000s in materials and fabrication methods.
Cross-country skis manufactured with Hexcel carbon fiber tapes. Photo Credit: Hexcel
The use of lightweight and high-performance materials in sports equipment continues to increase. According to a market report published by market research firm Lucintel (Irving, Texas, U.S.) in June 2020, the use of composite materials in the global sporting goods industry continues to grow, is expected to reach an estimated $579 million by 2023 and is forecast to grow at a CAGR of 3.2% from 2018 to 2023. Opportunities exist in a range of products including surfboards, skis and snowboards, bicycles, rackets, golf clubs, hockey sticks and fishing rods. Carbon fiber-reinforced polymer (CFRP) composites are expected to remain the largest segment over the forecast period, with glass fiber composites experiencing moderate growth as well. Over this period, Lucintel predicts that skis and snowboards will remain the largest application by volume and golf equipment the largest by value, with fishing rods seeing the most growth over the forecast period.
Carbon fiber composite bicycles
Bicycles continue to be the highest-profile market for composites use. In 2019, Arevo (Milpitas, Calif., U.S.) unveiled the world’s first 3D-printed carbon fiber unibody production bike frame at Eurobike 2019 in Friedrichshafen, Germany. In 2020, the company launched Superstrata, a direct-to-consumer Silicon Valley-based bicycle brand, said to be the world’s first made-to-measure, 3D-printed bicycle with an impact-resistant unibody carbon fiber frame.
The challenge the bicycle manufacturing industry faces, as reported in CW in “Safe cycling: Keys to composite design integrity,” is the lack of strictly enforced standards for the design and fabrication of carbon fiber composite bike frames. The lack of standards and oversight can and has led to substandard product quality, resulting in injury or death due to failure of composite structures. No legally binding structural safety standards yet exist that address common rider load and environmental conditions (braking, impact loads, fatigue, vibration, material aging or degradation, material abrasion and wear) for high-performance composite bikes. Further, the existing ASTM D-30 test methods are not yet recognized by ASTM’s F-08 Bicycle Committee.
The International Organization for Standardization (ISO, Zurich, Switzerland) published its ISO 4210 standard for bicycles — the most current standards for bicycle manufacture — in 2014 and 2015 in nine sections. ISO 4210 was “developed in response to demand throughout the world, and the aim has been to ensure that bicycles manufactured in compliance with this International Standard will be as safe as is practically possible. The scope has been limited to safety considerations and has specifically avoided standardization of components,” according to ISO.
Sustainability and customization
In watersports, ecological responsibility and sustainability continue to be a focus, and many fabricators are employing natural or reclaimed fibers and
bio-composites. A good example is Cobra International (Chonburi, Thailand), which is known for its sustainable technologies and products such as its CocoMat coconut fiber technology and bio-based surfboards. Another example is startup company JUC Surf (Jan Juc, Australia), which was founded in 2020 to build composite surfboards from recycled carbon fiber manufacturing scrap.
A growing trend toward customization, and high-end manufacturers’ desires to cater to the unique needs and desires of individual athletes, has opened the door to 3D printing. Krone Ltd. (Dallas, Texas, U.S.), for example, is employing the process in the manufacture of its top-end golf clubs, thanks to additive manufacturing expertise from CRP Group (Modena, Italy).
Composites in recreational vehicles
In another area of recreation, glass fiber composites are also used heavily for the exteriors of camping trailers and other recreational vehicles (RVs), the shipment of which are expected to have surpassed 400,000 wholesale units in the U.S. by the end of 2020 (a 4.5% increase over 2019) and see continued growth in 2021 to more than 500,000 units, according to an article published by the RV Industry Association (RVIA, Reston, Va., and Elkhart, Ind., U.S.) in September 2020. Despite a two-month shutdown in many North American manufacturing operations in early 2020 due to the coronavirus pandemic, the pandemic actually caused an increase in RV sales overall for the year, the RVIA says.
“The RV industry has experienced strong consumer growth over the past 10 years, but the recent soar in consumer interest in RVing, driven by the COVID-19 pandemic, has led to a marked increase in RV shipments to meet the incredibly strong order activity at the retail level,” says Craig Kirby, RV Industry Association president. “This new forecast confirms what we have been seeing across the country as people turn to RVs as a way to have the freedom to travel and experience an active outdoor lifestyle while also controlling their environment.” In an effort toward new composites innovation in recreational vehicles, in 2019, KZ Recreational Vehicles (Shipshewana, Ind., U.S.) tried out a prototype for a carbon fiber composite camping trailer, the Sonic X.
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