With the application of green manufacturing technology in cutting, it is a good choice to use compressed air cooling instead of cutting fluid cooling in high-speed milling. However, for specific high-speed milling tasks, which cooling method is more appropriate, it should be carefully weighed according to different processing purposes and materials to obtain the best processing results. The following are the four main process factors to consider when choosing a cooling method.
1 hardness of the workpiece material
If the hardness of the workpiece material is ≥ 42HRC, the choice of compressed air cooling usually achieves better results. High-speed milling of high-hardness materials is characterized by: 1 high cutting temperature; 2 chips will become harder than the parent material under cold work hardening. When cutting such materials, if the cutting fluid is cooled, the tool may be subjected to intermittent thermal rise-cooling, and the temperature change may easily cause the carbide cutting edge to break. Conversely, if compressed air is used, not only can the tool temperature be kept constant, but also the chips can be blown away from the cutting zone to avoid damage to the tool due to the secondary re-cutting of high hardness chips.
2 Types of workpiece materials
If the hardness of the workpiece material is < 42HRC, the cooling method should be determined according to the type of workpiece material. When milling high-speed viscous materials (such as aluminum, soft stainless steel, etc.), it is usually necessary to use cutting fluid to cool. The cutting fluid lubricates the tool and allows the chips to slide up and out of the chip pocket and separate from the tool's back corner. Compressed air cooling may be the right choice when milling most mold steels at high speeds (such as P20, H13, S7, NAK55, D2, etc.). If the workpiece material is found to be stuck to the tool during processing, it may indicate that a cutting fluid is required; however, it may be suggested that a different tool coating is required.
3 tool coating
Titanium Nitride (TiCN) coatings and TiAlN coatings are the two most commonly used tool coatings for high speed milling of tool steels. When the ball end mill mills workpiece materials with a hardness of less than 42HRC at a cutting speed of less than 245m/min (800sfm) (or the milling cutter mills the same material at a cutting speed of less than 600sfm), the tool is more suitable for TiCN coating. . If the hardness or cutting speed of the material to be processed is higher than the above cutting parameter range, it is preferable to use a TiAlN coating.
The TiCN coating has good adaptability to cutting fluid cooling. Although the sharp change in cutting temperature may still cause the carbide cutting edge to break, processing within the above cutting parameters does not generally produce a cutting high temperature sufficient to cause a thermal shock hazard.
Conversely, TiAlN coatings with good high-temperature cutting performance are not suitable for cutting fluid cooling. This coating provides a hard, smooth layer of alumina on the outer surface of the coating for high-temperature cutting, which helps to improve the cutting performance of the tool. (In fact, the “Exalon†TiAlN coating developed by Millstar in the United States is more advanced in high-temperature cutting performance. The TiAlN coating has a solid lubricating layer on the outside to make it easier for the chip to slide along the cutting edge of the tool. from.)
Milling of graphite electrode workpieces is generally less stringent on tool coatings. TiAlN coatings or diamond coatings are available. Although these two coatings use compressed air cooling to achieve good cutting results, many processing plants are still willing to use cutting fluids because the cutting fluid helps to remove dust from the machining process.
800*800mm Marble Porcelain Tiles
Marble Look Cermaic tile can not only maintain the nature marble texture,but also overcome the shortages of natural marble or stones.Also it meets people's pursuing quality of life for high-end decoration.Polished and Matte finishing stone look porcelain tiles are available,which can be widely used in interior floor and wall with size range of 80x80cm,400x80cm,40*40cm,20*80cm.
- Marble look porcelain tiles are produced by scanning by natural marble by 1:1 with 3D printing technology,which show the real effect of natural marble.
- Have good flatness and lower water absorption (less than 0.5%).
- Wear-resistant and stain resistance.
800*800Mm Marble Porcelain Tiles,Stain Resistance Porcelain Tiles,Marble Floor Tiles,Glazed Floor Tiles
Foshan Castel IMP&EXP Co.,Ltd , https://www.fscastel.com