Here are the important points to note when choosing cutting fluid for aluminum alloy cnc machining!

Compared with most steel and cast iron materials, aluminium has many significant physical properties: its strength and hardness are much higher than those of pure aluminium but lower than those of steel, it requires less cutting force, and has good thermal conductivity.

Due to the soft texture and strong plasticity of aluminum alloy cnc machining, it is prone to sticking to the tool during cutting, forming BUE on the tool. During high-speed cutting, welding may occur on the cutting edge, causing the tool to lose its cutting ability and affecting the machining accuracy and surface roughness. In addition, aluminium has a large coefficient of thermal expansion, and the cutting heat can easily cause thermal deformation of the workpiece, reducing the processing accuracy.

In conclusion, the selection of cutting fluid for cnc machining of aluminum alloys is of great significance. It must ensure good lubrication, cooling, filtration and anti-rust performance. Therefore, the cutting fluid for cnc machining of aluminum materials is different from ordinary cutting fluid, and choosing the appropriate cutting fluid is of vital importance.

According to the cnc machining conditions and precision requirements of aluminum alloys, different cutting fluids should be selected. Due to the fact that high-speed cnc machining generates a large amount of heat, such as high-speed cutting and drilling, if the heat produced cannot be carried away by the cutting fluid in time, the tool will stick to the workpiece, and even BUE may occur, which seriously affects the roughness of the workpiece and the tool life, and also causes thermal deformation of the workpiece, seriously affecting the accuracy of the workpiece. Therefore, when choosing cutting fluid, its own lubricity and cooling performance need to be taken into consideration.

For grinding, the grinding chips are very small, and a large amount of heat is generated during the grinding process. Therefore, both the lubrication and cooling performance of the cutting fluid and its filtration must be taken into consideration. If the viscosity of the selected cutting fluid is too high, the chips cannot be deposited or filtered out. They will scratch the surface of the workpiece processing area along with the circulation of the coolant, thereby affecting the processing of surface finish. Therefore, ultrafine grinding is selected for grinding or low-viscosity grinding oil or semi-synthetic cutting fluid grinding and reduction grinding.

When choosing cutting fluid, in addition to considering its lubrication, cooling and other properties, the corrosion resistance, cost and ease of maintenance of the cutting fluid should also be taken into account. Cutting oil is easy to choose base oil anti-friction additives with relatively low viscosity. This way, it can not only achieve lubricating friction but also have good cooling and easy filterability. However, cutting oil has problems such as low flash point, large smoke emission during high-speed cutting, high risk factor, rapid evaporation, and relatively high user cost. Therefore, when conditions permit, water-soluble cutting fluid should be used as much as possible.

For water-based processing fluids, it is more important to consider rust prevention. Nowadays, the commonly used water-based rust inhibitors include aluminum silicate and phosphate esters. For workpieces that are processed for a long time and stored during processing, a type of cutting fluid phosphate ester rust inhibitor is easily used. As a silicon-based material, when in prolonged contact with aluminum, it causes corrosion and the appearance of black "silicon spots". The ph value of the cutting fluid should be maintained above 8 to 10. If rusting is not done well, aluminum materials are highly prone to corrosion under alkaline conditions. Therefore, water-soluble cutting fluid must have good anti-corrosion performance for aluminum.