Long, short carbon fiber 3D printing technology

3D printing technology using traditional composite carbon fiber

3D printing carbon fiber may be the most sought after additive manufacturing technology after metal And with the development of additive manufacturing, the latest development is that a printer that can use elusive materials has finally become a reality. However, not all carbon fiber 3D printers are a type. Some machines can use microscopic Chopped fibers are used to reinforce traditional thermoplastics, while others use continuous long fibers placed inside a base thermoplastic matrix (which is usually filled with chopped fibers) to create a 'skeleton' inside the part.

Introduction of carbon fiber

Carbon fiber is composed of a chain of carbon atoms arranged together and has a very high tensile strength. However, when we use them alone, their thin and brittle nature makes them easily broken in any practical application, so The value of self-existence is not high. However, when binders are used to group and adhere fibers together, the fibers distribute the load smoothly and form a very strong and lightweight composite. Among these, carbon fiber composites It is mainly in the form of sheet, pipe or custom molded features, and is widely used in aerospace and automotive industries where strength-to-weight ratio is dominant. Moreover, the adhesives traditionally used are mostly thermosetting resins.

Carbon fiber printing technology

With the development of 3D printing technology, we can make 3D printing (recent advances 3D printing technology) use of carbon fiber. However, unlike the standard carbon fiber technology places on the different adhesive material used. Due to previously used adhesive The thermosetting resin does not melt, so it cannot be extruded through the nozzle (ie, it cannot be used in 3D printing technology), so in order to solve this problem, 3D printers replace thermosetting resins with easy-to-print thermoplastics Although these printed parts are not as heat resistant as resin matrix carbon fiber composites, they do enhance the strength of thermoplastics due to the incorporation of carbon fibers.

Chopped carbon fiber print vs continuous carbon fiber print

There are currently two carbon fiber printing methods: chopped carbon fiber filled thermoplastics and continuous carbon fiber reinforced materials. Among them, on the one hand, shredded carbon fiber filled thermoplastics are printed on standard FFF (FDM) printers, the main component of which is thermoplastic Plastic (PLA, ABS or nylon) and fine chopped carbon fiber. On the other hand, continuous carbon fiber manufacturing is a unique printing process that places continuous carbon fiber bundles into standard FFF (FDM) thermoplastic substrates.

Although carbon fiber is used in the manufacture of chopped carbon fiber-filled plastics and continuous fibers, the difference between them is enormous. So understanding how each method works and its ideal application will help you make informed decisions. What measures should you take in additive manufacturing?

Carbon fiber 3D printing - chopped carbon fiber filled thermoplastic

simply speaking, Chopped carbon fiber is a standard thermoplastic booster It allows companies to print generally weaker materials to increase their mechanical strength. The material is then mixed with a thermoplastic and the resulting mixture is extruded into a spool for the Filament Filament Manufacturing (FFF) process. For preparation by FFF Composite material, which is made up of short-cut fibers (usually carbon fibers) mixed with traditional thermoplastics such as nylon, ABS or PLA. Under the condition of FFF process, chopped fibers increase the strength, stiffness and increase of the model. The dimensional stability of the model, as well as the surface finish and precision.

This method is not only an advantage. Some short fiber reinforced fibers increase the strength by oversaturating the material. This not only damages the overall quality of the part, but also reduces the surface quality and part accuracy. So the prototype part and the end use part can be used short. Carbon fiber is manufactured because it provides the strength and appearance required for internal testing or customer-facing components.

Carbon fiber 3D printing - enhanced with continuous fiber

Continuous carbon fiber is the key to true reinforced composite strength The advantage of replacing traditional metal parts with 3D printed composite parts is that they can achieve similar strength over a small fraction of the weight, so in terms of efficiency, this is a cost-effective solution. Specifically, Using continuous filament manufacturing (CFF) technology inlaid in thermoplastics. Printers using this method print continuous high-strength fibers (such as carbon fiber) through a second printing nozzle in a FFF extruded thermoplastic. Fiberglass or Kevlar). This allows the reinforcing fibers to form the 'backbone' of the printed part, producing a hard, strong and durable effect.

Continuous carbon fiber not only increases strength, but also allows users to selectively reinforce areas where higher durability is required Due to the FFF nature of the core process, you can choose where to strengthen on a layer-by-layer basis. In each layer, there are two enhancements: concentric and isotropic. Concentric filling enhances each layer (internal and external) The outer boundary, and extends into the part by a user-defined number of cycles. Isotropic filling forms a unidirectional composite reinforcement on each layer, and carbon fiber weaving can be simulated by changing the direction of reinforcement on the layer. In general, these enhancements The strategy enables aerospace, automotive and manufacturing industries to integrate composite materials into their workflow in new ways. Printed parts can be used as tools and fixtures (all of which require continuous carbon fiber to effectively simulate metal properties.), Tools such as the end of the arm, soft palate, and CMM fixtures.

Today, the field of additive manufacturing has exploded, and some printers offer the ability to print on carbon fiber. However, it's best to pay attention to the composites you buy and the applications that each fiber has already opened. Unless it indicates that it is continuous Carbon fiber, otherwise this material is almost certainly composed of chopped carbon fiber reinforced filaments. While both offer independent value, being able to print both at the same time is the best way to meet all your application needs..