Development Prospects of CFRP in Aerospace Field
The rapid development of aerospace in recent years has gradually made it one of the pillar industries in my country.
Whether in civilian or military fields, the emergence of CFRP has brought revolutionary changes to aircraft manufacturing. The new aircraft made of carbon fiber composite materials has a smoother and more uniform surface than traditional aircraft, and the air resistance encountered during high-speed flight is significantly reduced. The speed per hour will also be increased. The most important thing is that CFRP has a high specific strength and specific rigidity, and the lightweight effect is very obvious. This material is 50% lighter than steel material and 30% lighter than aluminum material—widespread attention of manufacturing enterprises.
What is CFRP ?
Carbon Fiber Reinforced Composite is called Carbon Fiber Reinforced Polymer (CFRP). Carbon fiber refers to the high strength and modulus fiber with more than 90% carbon content. High-temperature resistance in the first of all chemical fiber. With acrylic fiber and viscose fiber as raw materials, through high-temperature oxidation carbonization. It is an excellent material for manufacturing aerospace and other high-tech equipment.
Carbon fiber is mainly composed of carbon elements because its graphite microcrystal structure along the fiber axis preferred orientation, so along the fiber axis direction has high strength and modulus.
The features of CFRP are as follows:
1. High strength (5 times stronger than steel).
2. Excellent heat resistance (can withstand high temperatures above 2000°C).
3. Excellent thermal shock resistance.
4. Low thermal expansion coefficient (small deformation).
5. Small heat capacity (energy saving).
6. Small specific gravity (1/5 of steel).
7. Excellent corrosion and radiation resistance.
How to solve the cutting problem of CFRP with PCD tools？
At present, carbon fiber has been recognized as an ideal material to replace aluminum alloy to manufacture aircraft. However, carbon fiber composites (CFRP) are difficult to machine due to their high hardness, low interlaminar shear strength, and low thermal conductivity. The difficulty of its processing is that the delamination and damage that are easily generated during cutting will have a more significant impact on the life of the tool.
Therefore, to solve the cutting problem of carbon fiber composite materials (CFRP), the tool's service life must be solved first.
After a series of experimental verifications of machining, it is found that cutting with polycrystalline diamond (PCD) can greatly improve the surface quality of carbon fiber composites (CFRP), promote the use of turning instead of grinding, and improve production efficiency.
Case Study of PCD Tool Machining CFRP Materials
Machining carbon brazed composite (CFRP) wing parts. Aviation companies generally take a confidential approach to machined parts. The original plan is a special carbide end mill for composite material processing. The dry cutting method is adopted, and the surface roughness of the parts is required to reach Ra1.2μm.
Compared with the original solution, the milling cutter using PCD solder pads increases the linear speed by 81%, the feed per revolution by 42%, and the processing technology and cutting allowance remain unchanged. As a result, the tool life of our company can reach 5 times that of cemented carbide tools, and the machining efficiency is also significantly improved, and the machined surface quality is better.
|
Brand |
More Super Hard | Carbide milling tools | |
|
Specification |
Φ10 |
Φ10 |
|
|
VC（m/min） |
471m/min |
260m/min |
|
|
F（mm/rev） |
0.1 mm/rev |
0.07 mm/rev |
|
|
Ap（mm） |
2~5mm |
2~5mm |
|
Remarks: More Super Hard tools are 5 times longer than existing tools.
