The markets: Sports and recreation (2020)
In 2019, Arevo unveiled the world’s first 3D-printed carbon fiber unibody production bike frame. Source | 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 to great fanfare — and sales. Golf 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.
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 early 2019, 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.
3D-printed thermoplastic bicycle rims. Source | Arevo
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. The company also produces a 3D-printed thermoplastic rim. The bicycle components were produced via the company’s “Arevo DNA” technology, which is an additive manufacturing (AM) process featuring patented software algorithms that are said to enable generative design techniques, free-motion robotics for “true 3D” construction, and direct energy deposition for virtually void-free construction optimized for anisotropic composite materials. Arevo says its process takes the design and final manufacture of a bike frame from 18 months to a few days, and results in significantly reduced production costs. Additional benefits are said to include the capability for serial, volume production of AM-made composite parts, automation and the ability for localized “on-demand” manufacturing and customization. (Learn more.)
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.
HIA Velo worked with Innegra Technologies to incorporate Innegra S high-modulus polypropylene fabrics, sized for compatibility with epoxy resin, to discrete areas of the Alfa bike frames to improve frame durability. Source | HIA Velo
With that said, there are plenty of bicycle manufacturers that take safety seriously. A good example is HIA Velo (Little Rock, Ark., U.S.), which combines composite materials to make its products more durable. HIA Velo worked with Innegra Technologies (Greenville, S.C., U.S.) to incorporate Innegra S high-modulus polypropylene fabrics, sized for compatibility with epoxy resin, to discrete areas of the Alfa bike frames to improve frame durability (learn more). Similarly, Derby Rims LLC (San Anselmo, Calif., U.S.) makes bicycle rims (wheels) that combine carbon fiber and high molecular weight polypropylene (HMWPP) for greater toughness (learn more).
Source | Cobra International
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. Its CocoMat coconut fiber technology and bio-based surfboards meet the highest ECOBOARD requirements set by Sustainable Surf and carry the ECOBOARD GOLD logo. (Learn more.)
Source | Krone Ltd.
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. Faced with exacting limits of club size and weight, and increasing demand from golfers for improved driver performance (ball distance, loft, speed and spin), “feel” and balance, company founder Mark Kronenberg approached the CRP Group (Modena, Italy), which had years of experience with 3D printing in Formula 1 racing. CRP Group companies include CRP Technology, which produces additive manufacturing materials and technology, and CRP Meccanica, with high-precision CNC machining experience.
The three companies worked together to develop the KD-1, a composite driver club head that consists of an additively manufactured body, using selective laser sintering (SLS) and employing Windform SP, a sinterable carbon fiber/polyamide powder; a Ti6A14V titanium strike face, CNC-machined from billet material, followed by sandblasting and cleaning; and a brass weight, also CNC-machined and sandblasted. Printable in hours, the hollow body’s lattice geometry optimizes its stiffness, while the carbon fiber/polyamide exhibits high ductility and impact absorption. The machined titanium face fits over and is adhesively bonded to the body. Four Helicoil inserts in the body, opposite the face, accept fasteners that attach a brass weight. According to Krone, the AM process coupled with CNC reduces the touch labor otherwise required for conventional composite driver heads made with prepreg, and produces parts with tighter tolerances than those made from cast and forged metals, without time- and labor-intensive secondary operations.
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