People are paying more attention to the issue of lightweight and the trend to satisfy the more secure, energy-saving, environmentally friendly, and comfortable demands. Carbon fiber is a material that has the advantages of being high-strength and lightweight. At present, the use of carbon fiber cloth has become gradually mature and marketable, but its molding is difficult, and the labor cost for the process is high. Therefore, the process of carbon long-fiber injection molding has become mainstream, and it can produce complicated components and improve structural strength.

Advantages of Carbon Long-fiber Injection Molding

At present, the process of fiber injection molding includes the combination of short fiber and resin SFT, the combination of long fiber and resin aggregate LFT-G, as well as the combination of continuous long fiber and resin LFT-D, FCS and LFT-D (Long Fiber Thermoplastic Direct) application injection molding. The finished product of fiber with a fiber length of more than 12 mm is tested in the target test. It is observed from photo 1 that short fiber (0.1~1 mm) can only sustain the structure stiffness of the finished product; when the fiber length is increased (10 mm~50 mm), it can not only sustain the structure stiffness but also improve the strength of materials; the continuous fiber (more than 50 mm) can improve the toughness of the finished product, and FCS target can improve the structure stiffness of the finished product as well as the strength of materials.

Photo 1- Diagram for the relationship between fiber length and stiffness, strength, and toughness

The Injection Unit Required for Carbon Long-fiber Injection Molding

The unit equipment (see photo 2) required by long fiber application injection molding has a special barrel, so it is necessary to match the following equipment to realize long fiber injection molding:

1. VENT barrel: The VENT barrel is a free-drying molding barrel. A characteristic of this barrel is that it can mold undried plastic raw material; the special design of the barrel can exhaust the steam and gas in the plastic raw material, and meanwhile, the continuous fiber is input through the exhaust vent.
2. HUNGRY FEEDER: the exhaust vent is designed in the middle of the VENT barrel. If a large amount of plastics enters through the feeding hole, it will cause the plastics to discharge from the exhaust vent, so it is necessary to install HUNGRY FEEDER to control the feeding.
3. FIBER ROVING: different from the short fiber molding, the long fiber injection molding needs to use the input of the continuous fiber.

Photo 2- Diagram for the framework of carbon long-fiber injection molding units

Photo 3- Flow chart for the test of carbon long fiber application injection molding

According to the test result, the fiber length has reached the target length of 12 mm set by FCS. The carbon fiber injection molding mainly focuses on energy and lightweight industry, thus, this technology will be introduced to the clients related to carbon fiber application industry, to help them solve the difficulty in long fiber injection process, so as to improve the product value of long fiber injection molding.

>>Read Full LFT-D Test Report
>>Extensive Reading-FCS Pursues Production of Smart, Lightweight, and High-Quality Cycling Accessories.