Comparison of Different Carbon Fiber Weaves

Comparison of Different Carbon Fiber Weaves

When talking about carbon fiber products, many people firstly know that products or things with carbon fiber texture are cool and fashion, also it looks really high-technology. Therefore, there are many products pursuing the appearance of carbon fiber texture. The most common type of carbon fiber on Taobao.com is the carbon fiber sticker. This is a sticker printed with the carbon fiber texture. It has nothing to do with the carbon fiber. But using carbon fiber texture as an adornment can be overkill. In fact, under the small lines of carbon fiber, there are huge secrets. Today we will discuss the difference between different carbon fiber textures to make carbon fiber products.

First of all, we know that when carbon fiber is manufactured, it is not produced one by one, but one by one, so the amount of carbon fiber contained in each bundle may be slightly different, but it can usually be divided into 1,000 and 3000 , 6000 roots, 12000 roots, which are the familiar concepts of 1k, 3k, 6k, 12k and so on.

Carbon fiber often comes in the form of a woven fabric, which makes it easier to use and provides additional strength depending on the application. Therefore, there are many weaves for carbon fiber fabrics. The most common are plain weave, twill weave and satin we will go into detail separately.

Plain Weave 

plain weave carbon fiber board looks very symmetrical and has a small checkerboard style look. In this weaving, the tow is knitted in an up / down pattern. The spacing between the interlaced tows is very small, which makes the plain weave very stable. Fabric stability is the ability of a fabric to maintain its weaving angle and fiber orientation. Due to its high stability, plain weave is not suitable for stacks with complex contours, it will not be as flexible as some other weaves. Generally, plain weaves are suitable for the appearance of flat plates, pipes and 2D curvilinear structures.

One disadvantage of this weaving pattern is that the crimp in the tow is very large due to the short distance between the interweaves (the angle of the fiber formed during weaving, see the figure below). This bending creates stress concentrations that weaken the part over time.

Twill Weave

Twill is a weave between plain weave and satin weave, which we will discuss below. Twill has good flexibility, can be formed into complex contours, and is worse than satin weave in maintaining fabric stability, but not as good as plain weave. If you follow a tow in a twill weave, it will pass through a certain number of tows and then the same number of tows. The top / bottom pattern creates the appearance of a diagonal arrow, called a "twill line." Compared to plain weave, the longer the distance between the drag staggers means less curl and less potential stress concentration.

2x2 twill is probably the best known carbon fiber weave in the industry. It is used in many exterior and decorative applications, but it also has excellent features, with moderate formability and moderate stability. As the 2x2 name indicates, each tow will go through 2 tows and then up through 2 tows. Similarly, a 4x4 twill will go through 4 tows and then up through 4 tows. It has a slightly higher formability than a 2x2 twill because it is less tightly knitted but less stable.

Satin weave

Satin weaves have a long history in fabrics, and were used early to make silk fabrics with excellent drape, while also looking smooth and seamless. For composite materials, this drape means it can easily form and wrap complex contours. Due to the easy formability of the fabric, its stability is low. Common harness satin weaves are 4 harness satin (4HS), 5­ harness satin (5HS) and 8 harness satin (8HS). As the number of satin weaves increases, formability will increase and fabric stability will decrease.

The numbers in the harness satin name indicate the total number of tows passing up and down. For 4HS, it will go more than 3 tows up and then pass 1 tow down. For 5HS, it will pass more than 4 tows up and then pass 1 tow down, while 8HS will pass 7 tows up and then 1 tow down.

Unidirectional cloth

Unidirectional cloth industry is also called UD cloth. As the name implies, uni means one, and all fibers are facing the same direction. This gives unidirectional (UD) fabrics some high strength advantages. UD fabrics are not woven fabrics and there are no crimped interwoven tows. Only highly oriented continuous fibers can increase strength and stiffness. Another benefit is the ability to control product strength by adjusting the layup angle and layup ratio. A good example is the use of unidirectional cloth to optimize the ply structure of a bicycle frame to adjust performance. The frame must maintain stiffness and stiffness in the area of the bottom bracket to transmit the driver's power to the wheels, but the frame also needs to have some flexibility and flexibility. With a unidirectional cloth, you can choose the precise direction of the carbon fiber to get the strength you need.

Good articles should be shared with everyone for learning.

(Cr:碳纤维研习社)