Selection, use and maintenance of cnc cutting fluid for aluminum alloy machining
Compared with most steel and cast iron materials, aluminum has many remarkable characteristics in physical properties: its strength and hardness are much higher than that of pure aluminum, but it is lower than steel, its cutting force is smaller, and its thermal conductivity is good.
Because aluminum alloy CNC machining is soft, plastic and easy to stick to the cutter, BUE is formed on the cutter, and fusion may occur on the cutter edge during high-speed cutting, which makes the cutter lose cutting ability and affects machining accuracy and surface roughness. In addition, the thermal expansion coefficient of aluminum is large, and the cutting heat easily leads to thermal deformation of the workpiece, reducing the machining accuracy.
Cnc cutting fluid for aluminum alloy machining
To sum up, the selection of cutting fluid for aluminum alloy CNC machining is very important, and good lubrication, cooling, filtering and rust prevention performance must be guaranteed. Therefore, the cutting fluid for aluminum CNC machining is different from ordinary cutting fluid, so it is important to select a suitable cutting fluid.
Different cutting fluids should be selected according to the machining conditions and accuracy requirements of aluminum alloy cnc. High speed CNC machining will generate a lot of heat, such as high-speed cutting and drilling. If the generated heat cannot take away the cutting fluid in time, the tool will stick, and even BUE will occur, which will seriously affect the processing roughness and tool life of the workpiece, and will also cause thermal deformation of the workpiece, seriously affecting the accuracy of the workpiece. Therefore, the choice of cutting fluid needs to consider its own lubricity and cooling performance.
For grinding, the wear debris is very small, and a lot of heat will be generated during the grinding process. Both the lubrication and cooling performance of the cutting fluid and the filtration of the cutting fluid should be considered. If the viscosity of the selected cutting fluid is too high, the chips cannot be deposited or filtered off. It will scratch the surface of the workpiece processing area with the circulation of the coolant, thus affecting the processing of the surface finish. Therefore, ultra-fine grinding is selected as grinding or low viscosity grinding oil or semi synthetic cutting fluid grinding to reduce wear.
When selecting cutting fluid, in addition to the lubricating and cooling properties of cutting fluid, the corrosion resistance, cost and maintainability of cutting fluid should also be considered. Cutting oil is easy to choose base oil antifriction additives with relatively low viscosity, which can not only achieve lubrication and friction, but also have good cooling and easy filtration. However, cutting oil has some problems, such as low flash point, large smoke during high-speed cutting, high risk factor, fast volatilization, and correspondingly high user cost. Therefore, if conditions permit, water-soluble cutting fluid should be used as far as possible.
For water-based processing fluid, it is more important to consider rust prevention. The commonly used water-based antirust agents are aluminum silicate and phosphate. As a kind of cutting fluid phosphate antirust agent, which is easy to use when the workpieces are stored for a long time in processing, black "silicon spots" will appear when the silicon based materials and aluminum are exposed to corrosion for a long time. The ph value of the cutting fluid is kept above 8~10. If the rust is not good, the aluminum is easily corroded under alkaline conditions. Therefore, the water-soluble cutting fluid must have good aluminum corrosion resistance.Aluminum alloy CNC processing factory
2、 Application and maintenance of cnc cutting fluid for aluminum alloy
The formula and use of cnc cutting fluid for aluminum alloy machining are basically the same as those of ordinary cutting fluid, but the selection of dilution water is more strict. Because many aluminum ions in the water will cause corrosion, if the content of these ions is too high, the antirust performance of the cutting fluid will be reduced, especially rust in the processing room, such as chloride ions, sulfate ions and heavy metal ions. In addition, some ions will react with the antirust agent of the aluminum cutting fluid, reducing the antirust property and stability of the cutting fluid, such as calcium and magnesium ions. Therefore, dilution water with low hardness or ion exchange water after dilution shall be selected as far as possible to soften, so as to ensure the service effect and life of cutting fluid.
In addition to the daily maintenance of the cutting fluid, the following points should also be noted:
1. Filtering
Due to the stability of aluminum soap reaction of aluminum alloy, the cutting fluid is easy to be damaged under alkaline conditions. The aluminum chips, aluminum chips and cutting fluid should be filtered immediately to avoid the reaction again, which will affect the service effect and life of the cutting fluid. The aluminum chips produced in the grinding process are small and light, so it is difficult to continue to precipitate. If the aluminum chips are not filtered or not filtered sufficiently, the aluminum chip processing area will be taken away with the cutting fluid circulation system, and the scratch surface will affect the glossiness of the processing surface.
2. Ph value
Because aluminum cutting fluid is very sensitive to the ph value, the ph value of aluminum cutting fluid shall be tested regularly, and it shall be adjusted in time in case of any abnormality. The ph value shall be controlled at 8-9 to avoid excessive corrosion of the workpiece or bacterial reproduction caused by low ph value, which will affect the stability and performance of the cutting fluid.
3. Add new scheme regularly
It can not only ensure good lubricity of cutting fluid, but also ensure good rust and corrosion resistance of cutting fluid, so as to prolong the service life of cutting fluid.
conclusion
It is very important to select the cutting fluid for aluminum alloy CNC machining. It should not only ensure the good lubricity and corrosion resistance of the cutting fluid, but also have good stability, filtration and easy maintenance. Only in this way can the requirements for machining products be met and the cutting cost of the body fluid be minimized.
