The processing of high-hardness materials places higher requirements on the performance of the milling cutter, and it is necessary to select specially designed CNC tools to ensure processing efficiency and precision. Common types of milling cutters include carbide milling cutters, ceramic milling cutters and cubic boron nitride (CBN) milling cutters. These cutters have extremely high hardness and wear resistance and are suitable for processing high-hardness materials such as hardened steel and titanium alloys.
Characteristics of High-hardness Materials
Common high-hardness materials include: chilled cast iron, hardened steel, powder metallurgy materials and other special materials. Processing characteristics of high-hardness materials:
- The hardness of high-hardness materials is generally above HRC45 and can reach HRC68. It has the characteristics of high strength and low plasticity.
- The blade is easy to break and wear quickly. During the cutting process, the contact time between the chip and the blade is short. The cutting force and cutting heat are concentrated on the edge, resulting in chipping and wear.
- The thermal conductivity is poor, and the cutting heat is difficult to dissipate through the chips, resulting in large cutting force and high temperature, aggravating tool wear, and easy to break or break the blade.
Requirements for Cutting Milling Cutters
To achieve cutting of high-hardness materials, the requirements for tools are very high. Both the tool material itself and the tool coating have high requirements. To ensure the performance and life of the tool. Therefore, the cutting tool must also have the following characteristics:
- Strong resistance to plastic deformation, that is, high temperature resistance and good hardness.
- Good chemical stability, that is, no chemical reaction with the cut material, oxygen, cutting fluid, etc., and no thermal decomposition.
- Good thermal conductivity and can resist high-temperature thermal shock.
End Mills Suitable for Processing High-hardness Materials
After continuous research and testing, SAMHO has launched two series of end mills that are very suitable for processing high-hardness materials. SHG and SHH series. The SHG series is suitable for processing high-hardness materials of HRC48-HRC62. The SHH series is suitable for processing materials of HRC65 and below, and its performance and life are 30% higher than the SHG series.
The SHG series 2-flutes ball nose end mill processes M333 heat-treated steel. After finishing for 5:30:45, it is used to process SKD11 (HRC60.5) high-hardness steel for 50 minutes, and the tool wear is still very slight.
