This wheel enables deep milling of difficult-to-cut composite fiber materials such as brake linings, architectural ceramic materials, secondary products of cement, carbon, FRP, and thermoset resins. The amount of ground material removed per unit time is relatively large, which realizes highly efficient grinding. By controlling the contact area between the material being ground and the wheel, this design reduces grinding noise, suppresses additional electric current in the main spindle, and contributes to energy saving.