Carbon fiber composite materials are constructed in a single molding process during production. Generally, they can only achieve a relatively regular shape and cannot achieve all the design features. This requires a large amount of secondary machining to complete the remaining design. For carbon fiber composite materials, the main secondary mechanical processing includes hole processing, special shape cutting processing, blind groove processing, and surface grinding processing.

The secondary processing methods of carbon fiber composite materials mainly include traditional mechanical processing and special processing. At present, traditional mechanical processing methods are still the main method of composite material processing, but more and more problems are encountered in the process of cutting. Problems such as rapid tool wear and delamination of drilling.

Practice has proved that because the properties of carbon fiber composite materials are different from metals, the processing tools and techniques of metal materials cannot be simply used in the processing of carbon fiber composite materials. Many researches mainly focus on the direction of drilling holes in carbon fiber composite materials. This is one of the key processing techniques of carbon fiber composite materials.

The drilling and processing characteristics of carbon fiber composite materials are mainly manifested in:

1. Carbon fiber composite material has low interlayer strength. During the drilling process, if the drilling axial force of the composite material component is too large, the interlayer stress will be too large. Exceeding the strength of the matrix resin will cause delamination and other defects ；

2. Carbon fiber composite material is an anisotropic material, and its fiber layer direction has a great influence on hole making, especially when making holes in unidirectional plates, the stress concentration at the hole is relatively large, which can easily cause defects such as splitting;

3. The carbon fiber composite material has high hardness, and the drill bit wears quickly when drilling;

4. The carbon fiber composite material has poor thermal conductivity. During the drilling process, the drill bit and the composite material generate a lot of friction heat. However, the carbon fiber composite material has a low thermal conductivity, and the heat is difficult to remove during processing, which causes the temperature in the cutting area to rise rapidly and accelerates the drill bit. Wear.

Technical measures to prevent fiber delamination at the exit end during drilling: Under the condition of an open structure, the exit surface of the hole should be supported and cushioned with a hard high-density board, which can effectively prevent delamination and splitting at the exit. When conditions permit, one or two layers of glass cloth can be added to the exit surface when manufacturing carbon fiber composite components, and the glass cloth will be solidified at the same time as the component. After the holes are drilled, the glass cloth will be torn off, which can also prevent The exit surface of the hole is stratified.