Cemented carbide milling cutter refers to a milling cutter made of cemented carbide. To understand cemented carbide milling cutters, you must first know what cemented carbide is. Cemented carbide is mainly composed of high-hardness, refractory metal carbides (WC, TiC) and micron-sized powders, with cobalt (Co) or nickel (Ni), Molybdenum (Mo) is a binder, powder metallurgy products sintered in a vacuum furnace or a hydrogen reduction furnace.
Cemented carbide milling cutter classification
Cemented carbide milling cutters are mainly divided into: solid carbide milling cutters | cemented carbide straight shank groove milling cutters | cemented carbide saw blade milling cutters | cemented carbide auger milling cutters | cemented carbide machine reamer milling cutters | Carbide End Mills | Carbide Ball End Mills
Carbide milling cutter use:
Carbide milling cutters are generally mainly used for CNC machining centers and CNC engraving machines. It can also be installed on an ordinary milling machine to process some harder and less complex heat-treated materials.
1. Carbide cylindrical milling cutter: used for processing planes on horizontal milling machines. The cutter teeth are distributed on the circumference of the milling cutter. According to the tooth shape, they are divided into straight teeth and spiral teeth. According to the number of teeth, there are two types: coarse teeth and fine teeth. The helical coarse-tooth milling cutter has a small number of teeth, high tooth strength and large chip holding space, which is suitable for rough machining; fine-tooth milling cutters are suitable for fine machining.
2. Carbide face milling cutter: used for machining plane on vertical milling machine, end milling machine or gantry milling machine. There are cutter teeth on the end surface and circumference, as well as coarse and fine teeth. Its structure has three types: integral type, insert type and indexable type.
3. Carbide end mills: used for processing grooves and step surfaces, etc. The cutter teeth are on the circumference and end surfaces, and cannot be fed along the axial direction when working. When the end mill has end teeth passing through the center, it can feed axially.
4. Cemented carbide three-side and face milling cutter: used to process various grooves and step surfaces, with teeth on both sides and circumference.
5. Carbide angle milling cutter: It is used for milling grooves at a certain angle. There are two types of single-angle and double-angle cutters.
6. Carbide saw blade milling cutter: used to process deep grooves and cut off the workpiece, with more teeth on the circumference. In order to reduce the friction during milling, there are 15’~1° secondary deflection angles on both sides of the cutter teeth. In addition, there are keyway milling cutters, dovetail milling cutters, T-slot milling cutters and various forming milling cutters.
Carbide milling cutter milling method
The feed direction of the carbide milling cutter relative to the workpiece and the rotation direction of the milling cutter mainly have the following two milling methods:
The first type is down milling. The rotation direction of the milling cutter is the same as the cutting feed direction. When the cutting starts, the milling cutter bites the workpiece and cuts off the final chips.
The second type is up-milling. The rotation direction of the milling cutter and the cutting feed direction are opposite. The milling cutter must slide on the workpiece for a period of time before starting to cut, starting with the cutting thickness as zero, and reaching the cutting thickness at the end of the cutting maximum.
During down milling, the cutting force presses the work piece against the worktable, and during up milling, the cutting force pushes the work piece away from the worktable. Because the cutting effect of down milling is the best, down milling is usually the first choice. Only when the machine has thread clearance problems or problems that cannot be solved by down milling, then up milling is considered.
Every time the carbide milling cutter blade enters the cutting, the cutting edge must bear an impact load. The load depends on the cross section of the chip, the workpiece material and the cutting type. Under ideal conditions, the diameter of the milling cutter should be larger than the width of the workpiece, and the axis of the milling cutter should always be slightly away from the centerline of the workpiece. When the tool is placed directly at the cutting center, it is very easy to produce burrs. When the cutting edge enters and exits cutting, the direction of the radial cutting force will continue to change. The spindle of the machine tool may vibrate and be damaged. The blade may be chipped and the machined surface will be very rough. The carbide milling cutter is slightly off-center, and the direction of the cutting force will change. No more fluctuations, the milling cutter will gain a kind of preload.
Carbide milling cutter maintenance
When the axis line of the cemented carbide milling cutter coincides with the edge line of the workpiece or is close to the edge line of the workpiece, the situation will be very serious. The operator should do the relevant equipment maintenance work:
1. Check the power and rigidity of the machine tool to ensure that the required milling cutter diameter can be used on the machine tool.
2. The overhang of the tool on the spindle is as short as possible to reduce the impact of the milling cutter axis and the position of the workpiece on the impact load.
3. Use the correct tooth pitch of the milling cutter suitable for the process to ensure that there are not too many blades meshing with the workpiece at the same time to cause vibration during cutting. On the other hand, ensure that there are enough blades when milling narrow workpieces or milling cavities. Engage with the workpiece.
4. Make sure to use the feed per blade so that the correct cutting effect can be obtained when the chip is thick enough to reduce tool wear. The indexable insert with positive rake angle groove shape is adopted to obtain a smooth cutting effect and the lowest power.
5. Select the diameter of the milling cutter suitable for the width of the workpiece.
6. Choose the correct entering angle.
7. Place the milling cutter correctly.
8. Use cutting fluid only when necessary.
9. Follow the tool maintenance and repair rules, and monitor tool wear.
Doing a good job in the maintenance of cemented carbide milling cutters can prolong the service life of the cutters and improve work efficiency.