Basic requirements of materials for cutting parts of milling cutters
1) High hardness and wear resistance: At room temperature, the material of the cutting part must have sufficient hardness to cut into the workpiece; with high wear resistance, the tool will not wear and extend the service life.
2) Good heat resistance: The tool will generate a lot of heat during cutting, especially when the cutting speed is high, the temperature will be very high, therefore, the tool material should have good heat resistance, even at high temperature It can maintain high hardness and has the ability to continue cutting. This kind of high-temperature hardness is also called hot hardness or red hardness.
3) High strength and good toughness: During the cutting process, the tool must withstand a large impact force, so the tool material must have a high strength, otherwise it is easy to break and damage. Because the milling cutter is subject to impact and vibration, the milling cutter material should also have good toughness so that it is not easy to chip and crack.
Common materials for milling cutters
1) High-speed tool steel (referred to as high-speed steel, front steel, etc.) is divided into general-purpose and special-purpose high-speed steel.
It has the following characteristics:
a. The content of alloy elements tungsten, chromium, molybdenum and vanadium is high, and the quenching hardness can reach HRC62-70. At a high temperature of 600 ℃, it can still maintain a high hardness.
b. The cutting edge has good strength and toughness, strong vibration resistance, and can be used to manufacture cutting tools with average cutting speed. For machine tools with poor rigidity, high-speed steel milling cutters can still be used for smooth cutting.
c. The process performance is good. Forging, machining and sharpening are relatively easy. It is also possible to manufacture tools with more complicated shapes.
d. Compared with cemented carbide materials, it still has the disadvantages of lower hardness, poor red hardness and poor wear resistance.
2) Cemented carbide: It is made of metal carbide, tungsten carbide, titanium carbide and cobalt-based metal binder through powder metallurgy process.
