Selection of CNC machining tools and cutting fluid
First, according to the tool material
1. Tool steel tool:
The heat resistance is poor, and the cooling effect is required, and the emulsion is preferably used.
2. High-speed steel tool:
The maximum temperature can reach 600 ° C. When cutting at low speed and medium speed, an oil-based cutting solution or an emulsion is selected. When cutting at high speed, since the amount of heat generation is large, the water-based cutting fluid is selected.
3. Cemented carbide tool:
The maximum allowable operating temperature can reach 1000 ° C, and the oil-based cutting fluid containing anti-wear additives is selected. Be careful to cool the tool evenly, before cutting, cool the tool in advance. High-speed cutting, to use large flow cutting oil spray cutting zone to reduce the tool of the tool is unevenness and produce a strapping, and can reduce the smoke.
4. Ceramic tool:
High temperature wear resistance is the highest, generally using dry cutting, and water-based cutting fluids can also be used.
5. Diamond Tool:
It has extremely high hardness, generally used dry cut. In order to avoid excessive temperature, water-based cutting fluid is employed as a ceramic material.
Second, the selection and maintenance of aluminum alloy cutting fluid
1. Characteristics of aluminum and aluminum alloy
1) Aluminum, aluminum is soft, large, deformable during cutting, easy to stick to the knife, forming a chip tumor on the tool, possibly dissolving the weltable capacity, affecting the cutting capacity, affecting processing accuracy and surface roughness.
2) The thermallation coefficient of the aluminum alloy is large, and the cutting heat can easily cause the working heat deformed, and the processing accuracy is reduced.
3) The surface is easily discolored and pore, and the surface brown changes into black, which will precipitate white powder, commonly known as white rust.
2. Choice of aluminum alloy cutting fluid
It is necessary to take into account the lubricity, and it is also considered that it is desirable, and the emulsified cutting solution or low viscosity of the cutting fluid is selected.
3. Aluminum alloy grinding processing
Since the grinding is very small, it is necessary to pay attention to the filtering property of the cutting fluid. The thickness of the grinding liquid cannot be selected. Otherwise, the chips cannot be deposited in time or filtered out, and the surface of the workpiece is scratched and affects the surface finish. It is therefore easy to use precision grinding oil or semi-synthetic cutting fluid for fine grinding or superfine milling.
4. Use and maintenance of aluminum alloy cutting fluid
1) Use tap water, preferably deionized water to ensure the use of cutting fluids and life.
2) The machine tool must have a filtration system, minimize the cleaning of the filter or non-woven fabric at least 3 days. Because aluminum alloy is easy to form aluminum soap, the stability of cutting fluid is destroyed. Aluminum chop should be filtered immediately to avoid the effect and life of aluminum chips. During the grinding process, the aluminum chips are both small and light, it is difficult to precipitate, such as not filtration or filtration is not sufficient, the aluminum chips will scratch the machining surface, affect the surface gloss.
3) pH. The aluminum material is very sensitive to the pH of the cutting fluid. It is necessary to detect the PH value of the cutting fluid. It is found that the abnormality should be adjusted in time, so that the pH is controlled between 8-9, so as to avoid the pH of the corrosion workpiece, pH value It is too low to breed a large number of bacteria, affecting the stability and performance of the cutting fluid.
4) Timed add new fluid. That is to ensure good lubrication of the cutting fluid, it also ensures good rust resistance and sterilization resistance of cutting fluid to extend the life of the working fluid.
5) Pay attention to the method of formulation of new fluids, but also pay attention to when dilute, pay attention to the method of depth management.