Composite 3D printing is an emerging additive manufacturing technology for applications in various industries. Currently, the main fibers used are carbon fiber, glass fiber, and Kevlar. Carbon fiber has an excellent strength-to-weight ratio and high stiffness, making it suitable for industries such as aerospace, automotive, and construction. Fiberglass is cost-effective and widely used in a variety of applications. Kevlar is a durable fiber with high strength and heat resistance, suitable for the manufacture of parts subject to vibration and abrasion resistance.
At the heart of composite 3D printing is the composite material itself, which is made of at least two components and has special properties that make it suitable for 3D printing applications in various industries. In recent years, composite 3D printing technology has become more and more popular. Many companies are starting to use this technology. It is estimated that by 2030, the composite material 3D printing market will reach 1.73 billion US dollars (about 12.6 billion yuan).
3D printing composite materials
How has the development of 3D printing of composite materials promoted innovation and development in aerospace, automotive, construction, and other industries? What are the potential challenges and opportunities for the application of these materials in 3D printing?
At present, people have achieved large-scale 3D printing of aerospace composite structural parts
carbon fiber reinforcement
As mentioned earlier, carbon fiber reinforcements are commonly used in the additive manufacturing of composite materials. Invented by chemist Joseph Swan in 1860, carbon fiber consists of interconnected carbon atoms forming a crystalline structure arranged in strands for exceptional stability. Known for its superior strength-to-weight ratio (twice that of aluminum), it is valuable for making lightweight yet strong end parts. In addition, the carbon fiber-infused material offers high stiffness, strong tensile strength, and effective chemical resistance.
However, the use of carbon fiber requires special considerations when using 3D printing technology. For example, using hardened steel print nozzles is critical to ensuring the production of high-quality parts. Similar guidelines apply to matrix materials combined with carbon fiber reinforcements. Various matrices such as PLA, PETG, nylon, ABS, or polycarbonate can be made stronger and lighter with the addition of carbon fibers. These fibers can be blended not only with thermoplastics but also with ceramics, helping to create novel applications. Industries such as aerospace, automotive, and construction all benefit from carbon fiber matrix composites, taking advantage of their unique properties.
MAMBO boat launched by Moi Composites
Glass Fiber Reinforced Composites
Introduced in 1930, glass fiber material can be used as a reinforcement material for many thermoplastic polymers. When combined with the proper substrate, it can create parts that are ten times stronger than ABS. Glass fiber composites are less rigid and brittle than carbon fiber composites. These properties, along with cost-effectiveness, have made glass fiber composites attractive. Fiberglass has excellent mechanical properties, acts as an effective electrical insulator, and has low thermal conductivity. The material is available in a variety of colors and has low shrinkage to minimize the risk of warping. Similar to carbon fiber, glass fiber-reinforced filaments are abrasive and require the use of nozzles suitable for this material.
Bridge component prototype printed with fiberglass
Glass fiber-reinforced 3D printing filaments have proven valuable for engineering prototypes and end-application parts that require strong mechanical properties and thermoelasticity. This composite material has been widely recognized in applications ranging from construction to marine and sports. Notable examples include Moi Composites’ collaboration with Autodesk, Catmarine, Micad, and Owens Corning to create the MAMBO boat using fiberglass 3D printing. Additionally, Dutch company MX3D has 3D printed a reinforced bridge using the material.
3D printing of Kevlar composites
Kevlar reinforced material
Kevlar is a trademark owned by DuPont and was first created in 1971 by Stephanie Kwolek. It belongs to the category of aramid fibers and is one of the most durable materials.
The material is obtained through polymerization, the process of linking long chains of molecules. Kevlar fibers are carefully arranged in parallel rows, which is attributed to its strong properties. Similar to other fibers, Kevlar fibers are often combined with various plastics for the manufacture of composite materials. Kevlar fiber exhibits commendable mechanical properties in terms of tensile strength and fatigue strength and is mainly used in the manufacture of components subject to strong vibration and requiring wear resistance. Remarkably, it has five times the strength-to-weight ratio of steel and has exceptional heat resistance up to 400°C.
3D printed self-charging electric car launching in 2020
Kevlar also has properties such as low density, versatile applications, and uniform molecular structure, which is conducive to 3D printing high-quality parts with special polishing. Many industries use Kevlar additive manufacturing. Notably, the automotive industry finds its value in applications for the manufacture of various components. A striking example is the use of this composite material by Aptera Motors in the US to 3D print car parts, highlighting the potential of reinforced materials in contemporary manufacturing.