Drilling nano-carbon fiber composite materials is a technical process, because many processing manufacturers with inaccurate processes can easily cause nano-carbon fiber materials to become delamination. What should be done when this happens? Let me explain the reasons for delamination in the processing of nano-carbon fiber composite materials.

Because when the drill bit cuts into the nano-carbon fiber composite material, the main cutting edge first peels off the fiber and then cuts it off. This peeling affects the outermost material at the entrance end of the hole. When the fiber is peeled off, the cutting edge of the drill bit must cut the fiber at the same time. Once it cannot be cut completely or the cutting force exceeds the strength of the matrix resin, cracks will occur and spread along the direction of the surface layer fiber, which is the entrance of the hole. Cause of cracking.

During the drilling process, the drilling axial force is applied to the surface of the carbon nanofiber material, so that each layer of the carbon nanofiber composite material receives a certain tensile force in the thickness direction, thereby generating interlayer stress in the material layer around the hole wall. If the interlayer stress is too large, delamination will occur. At the same time, the drilling force changes periodically, and the axial force also makes the material around the hole wall bear alternating stress, which increases the probability of delamination. For the plate, the greater the axial force, the greater the tensile stress between layers, and delamination also occurs.

During the drilling process, as the thickness of the nano-carbon fiber board material is getting lower and lower, the strength of the drilled hole continues to decrease. When the chisel edge of the drill touches the outermost fiber, it is equivalent to applying a thrust to the outermost material separating the other fiber layers. However, the chisel edge has a negative rake angle and is not sharp enough. Therefore, the fiber layer at the exit end of the hole is not cut, but retreats outward under the action of axial force. If the outermost fiber layer is not cushioned, the outermost fiber is very Easily torn from the substrate, causing splitting at the outlet.

It is known from the above analysis that the drilling axial force is an important factor affecting the quality of nano-carbon fiber composite holes, and is the main cause of delamination defects and exit splitting.