Matters needing attention when machining center processing composite materials

The machining center is a high-precision machining equipment, and the entire machining process is completed under the control of the CNC numerical control system. Some very unique composite materials can be processed. Now composite materials are widely used in all aspects of our lives, especially the ultra-precision machinery industry in the aircraft parts manufacturing industry! Composite materials often have the rigidity, thickness, weight, strength and other composite materials that ordinary materials do not have. They are greatly improved! What matters should the machining center pay attention to when processing composite materials?

Faced with the processing of these composite materials, we need to perform precise processing according to the types of composite materials.

Witford Tools briefly introduces the issues that should be paid attention to when processing composite materials in machining centers:

Composite materials are classified into metal and metal composite materials, non-metal and metal composite materials, and non-metal and non-metal composite materials according to their composition. According to its structural characteristics, it is divided into:

1. Fiber composite materials. It is composited by placing various fiber reinforcements in the matrix material. Such as fiber-reinforced plastics, fiber-reinforced metals, etc.

2. Sandwich composite materials. It is composed of different surface materials and core materials. Generally, the face material is high and thin; the core material is light and low in strength, but has a certain rigidity and thickness. There are two types: solid sandwich and honeycomb sandwich.

3. Fine-grained composite materials. Distribute hard fine particles evenly in the matrix, such as dispersion strengthened alloys, cermets, etc.

4. Hybrid composite materials. It is composed of two or more reinforcing phase materials mixed in one matrix phase material. Compared with ordinary single-reinforced phase composite materials, its impact strength, fatigue strength and fracture toughness are significantly improved, and it has special thermal expansion properties. It is divided into intra-layer hybrid, inter-layer hybrid, sandwich hybrid, intra-layer/inter-layer hybrid and super-hybrid composite materials.

Fiber composite

1. Carbon fiber composite material has low interlayer strength and is easy to produce delamination under the action of cutting force. Therefore, the axial force should be reduced when drilling or trimming. Drilling requires high speed and small feed. The speed of the machining center is generally 3000~6000r/min, and the feed rate is 0.01~0.04mm/r. The drill bit should be three-pointed and two-edged or two-pointed and two-edged. It is better to use a sharp knife The tip can cut off the carbon fiber layer first, and the two blades can repair the hole wall. The diamond-inlaid drill has excellent sharpness and wear resistance. The drilling of composite material and titanium alloy sandwich is a difficult problem. Generally, solid carbide drill bits are used to drill according to the cutting parameters of drilling titanium alloy. Relieve burns from composite materials. Boeing has specially developed a PCD combination drill bit for interlayer drilling.

2. The cutting effect of special milling cutters for machining of 2, 3 types of new solid carbide composite materials is better. They all have some common characteristics: high rigidity, small helix angle, even 0°, and specially designed herringbone blades can be effective. Reduce the axial cutting force of the machining center and reduce the delamination, and its processing efficiency and effect are very good.

3. The cutting chips of composite materials are powdery, which is harmful to human health. High-power vacuum cleaners should be used to collect dust. Water cooling can also effectively reduce dust pollution.

4. Carbon fiber composite material components are generally large in size, complex in shape and structure, and high in hardness and strength. They are difficult to process materials. During the cutting process, the cutting force is relatively large, and the cutting heat is not easily transmitted. In severe cases, the resin will be burnt or softened, and the tool wear will be serious. Therefore, the tool is the key to carbon fiber processing. The cutting mechanism is closer to grinding than milling. , The linear cutting speed of the machining center is usually greater than 500m/min, and the high-speed and small-feed strategy is adopted. Edge trimming tools generally use solid carbide knurled milling cutters, electroplated diamond particle grinding wheels, diamond-inlaid milling cutters, and copper-based diamond particle saw blades.

Recommended tools for machining centers when processing composite materials:

Due to the high hardness and rigidity of composite materials, we usually recommend cemented carbide materials to tools-milling cutters, drills, reamers, etc. Cemented carbide tools have the characteristics of extremely high hardness and high temperature resistance, and the high speed during cutting can make the surface of the processed composite material smooth and neat after the processing is completed.

Changzhou Weitefu Tools Co., Ltd. manufacturers custom all kinds of tungsten steel milling cutters, tungsten steel drill bits, tungsten steel reamers, tungsten steel forming knives and PCD tools, support non-standard tungsten steel tool customization, factory direct price discounts.