High-speed milling usually refers to milling at high spindle speeds and high feed rates (5 to 10 times that of conventional milling). Moderate spindle speeds and large cutter diameters can also achieve high-speed milling, which is 4 to 6 times that of conventional milling Cutting speed and feed speed finishing hardened steel parts also belong to high-speed milling. In mold manufacturing, high-speed milling can be used to process electrodes for EDM processing, or it can directly replace EDM processing for machining hardened mold parts.

So, what are the characteristics of high-speed milling? Please see below 6 points. 

1. High machining accuracy. High-speed CNC milling machines of high-speed machining centers generally have high rigidity and high precision. At the same time, high-speed milling generally uses high milling speeds, appropriate feed speeds, small radial and axial milling depths, because the cutting force is small and the thermal deformation is small, which can achieve high processing accuracy. 

2.The surface quality is high. When high-speed milling, the machining allowance is cut off immediately without sufficient deformation, and the residual stress on the surface of the workpiece is extremely small. Most of the heat generated during the milling process (more than 95%) is quickly taken away by the chips, The temperature of the workpiece is low, and there is no metamorphic layer on the processed surface. The excitation frequency of the high-speed rotation of the spindle is far away from the natural vibration frequency of the process system. When steel parts reach Ra0.2~0.4.

3. High production efficiency. The high cutting speed and feed speed increase the material removal rate per unit time. High-speed milling can process hardened steel parts, and the workpiece can be roughed, semi-finished, and finished at a time after clamping. High-speed milled workpieces can no longer be ground and polished.

4. Conducive to the use of smaller diameter milling cutters. High-speed milling is suitable for the use of small-diameter cutters, which can reduce the technical parameters of the cutters and save the cost of the cutters.

5. It can process complex and thin-walled parts. During high-speed milling, the lateral cutting force is very small, which is beneficial to the processing of complex mold parts and thin-walled parts. The wall thickness of the workpiece can be less than 1mm.

6. It can process hard or brittle materials. High-speed milling can mill hardened steel with hardness up to 60HRC and can also process brittle materials such as graphite.

P20 steel is commonly used in rapid tooling, this is hard steel and will need the high-speed milling process. Also, the suitable process methods also depend on the structure and size of mold. If you have the requirements of rapid tooling, feel free to contact us by email enquiry@nice-rapidtooling.com to get free quote.