Comparison of Three Forming Technologies for Carbon Fiber UAV

In the design and manufacture of carbon fiber composite UAV, the structural elasticity and stiffness distribution requirements are often realized by adjusting the laying angle and material layers. Carbon fibre composite is one of the reinforcement materials used by UAV at present. Making UAV with carbon fibre composite generally involves the following three forming processes:

Hot Pressing Tank Forming Technology

Hot-pressing tank forming is one of the high-performance forming processes for composite materials. For UAV with high speed requirements, this process is mostly used to manufacture composite components and main bearing components. Carbon fiber reinforced composites (CFRP) formed by hot-pressing tank have better internal quality, more uniform resin content and better mechanical properties. However, the hot-pressing tank forming technology also has some shortcomings, such as higher requirements for equipment, higher pre-investment and processing costs, and relatively poor economy. From the cost point of view, low temperature and low pressure forming technology is often chosen to replace the limited budget. In addition, the flow of resin, heat transfer, chemical crosslinking and void formation of carbon fiber composites will interact during the hot-pressing process, which increases the difficulty of process control. Once the process is mastered incorrectly, there will be processing defects such as poor glue, high porosity and so on. In order to ensure the quality of unmanned parts of carbon fiber composites, Wuxi Zhishang New Material Technology Co., Ltd. can control the pressure and temperature curves of hot-pressing tank process by simulating the phenomena of dynamic change, resin flow and heat transfer in the process of hot-pressing tank forming.

Vacuum Bag Forming Technology

 

Compared with the hot-pressing tank process, the vacuum bag forming process is relatively simple, and does not require excessive investment in the early stage, and the operation is moderately difficult. However, the pressure of this forming method is small, and it is only suitable for composite components with low quality standards. It is mostly used to manufacture honeycomb sandwich structure and laminate structure with less than 1.5mm. Because of the obvious cost advantage, this technology is widely used in the manufacture of low-speed UAV, because in the manufacture of small low-speed UAV, vacuum bag forming technology can meet the production requirements of most parts.

In practice, because the vacuum bag forming process needs preprepreg paving, wet paving and other processes, and the wet operation is affected by human factors, easy to lead to uneven glue painting, this situation is particularly evident in sandwich structure forming. In addition, the unreasonable brushing direction can easily lead to the bending and change of the fiber direction, which threatens the stability of carbon fiber composite parts. Wuxi Zhishang New Material Technology Co., Ltd. adopts preprepreg paving, which can effectively avoid the above problems and improve the stability of the parts.

compression molding

The molding process is more suitable for the manufacture of foam sandwich composite components. It combines the advantages of autoclave molding technology and vacuum bag molding process, and has high production efficiency, large molding pressure, equipment investment and moderate cost, and good economic performance. Most of the parts with foam sandwich structure such as UAV rudder and so on adopt the molding process. In the manufacture of carbon fiber UAV wing plate, the molding process can also ensure the appearance quality and wing accuracy of UAV wings, and improve the overall manufacturing quality of UAVs. However, pressure control is the most critical process of this process. Wuxi Zhishang New Material Technology Co., Ltd. can more accurately determine pressure control parameters and ensure the performance level of structural parts through structural analysis and long-term experience summary.

The application of carbon fibre composites is an important trend in the development of UAV manufacturing. It is also an effective way to meet the requirements of UAV’s voyage, voyage time, voyage height, manufacturing cost and concealment. Carbon fiber composite UAV structure design and manufacturing process optimization is the key to the application of carbon fiber UAV. The former needs the efforts of UAV designers, and the latter needs continuous attempts and innovations in the development and application of carbon fiber composite materials. The increasing proportion of carbon fibers used in UAV will effectively improve the manufacturing level of UAV in China.