How to control the hole-making quality of carbon fiber products?

Carbon fiber composite materials have good physical and mechanical properties, and are widely used in the aviation industry, industrial manufacturing, medical equipment, and sports articles. When the carbon fiber composite material is used as the main bearing structure, it is mostly mechanically connected to the metal material. However, the anisotropy of the carbon fiber composite material has a serious impact on the quality of the hole.

In the holes drilling of carbon fiber products, delamination, burrs and tearing of the hole edges are very common defects. Burrs and tears usually exist in the fiber layer on the upper and lower surfaces of carbon fiber products. Among them, the delamination and tearing of the hole edges not only affect the quality of the assembly, but also have a very bad effect on the overall structural stress.

Researchers have studied the cutting mechanism of carbon fiber composite materials and found that the structure of the tool has a significant effect on the cutting morphology, cutting force and cutting heat. Reasonable tool structure design can not only increase its service life, but also has important significance for improving the quality of carbon fiber products.

The drill point angle and the helix angle are important geometric parameters of the cutting tool twist drill, which have a great influence on the quality of the carbon fiber board. Researchers conducted a large number of research parameter comparisons and found that the sharp angle has a greater impact on the chip discharge angle, cutting force, burrs and hole wall roughness. Comparing the drilling performance under different drill point angles, they found that the hardness is high and toughness. For poor CFRP, you need to select a smaller point angle.

During the drilling process, the chisel edge on the twist drill will not only accelerate the wear of the tool, but also an important factor that causes delamination of the carbon fiber product hole edge. The researchers found that the chisel edge accounts for 40%-60% of the axial drilling force. The chisel edge can be optimized to reduce the effect and improve the quality of the hole edge. Straight flute drills are suitable for processing materials that will not produce long tendril-shaped cutting. Carbon fiber composite materials are just right. Straight flutes can quickly discharge the debris generated after processing. Small drill point angles can prevent delamination of the exit and improve hole processing quality.

The optimization of the geometric parameters and shape of the hole-making tool not only improves the hole-making quality of carbon fiber composite materials, but also extends the service life of the tool. With the development of more and more high-modulus carbon fiber products, the difficulty of making holes is also With this increase, some composite structures of carbon fiber and metal materials have appeared, which puts forward higher requirements on the design of the tool.