Why did cutting nodules occur during Dongguan CNC machining

When machining with Dongguan CNC, the cutting amount is still small and the feed speed is not so fast. Why is the accuracy lower than when rough machining? Before discussing this issue, let's first popularize a term called cutting tumor.

I believe that the technical personnel who are truly skilled in dry machining are not unfamiliar. Simply put, the cutting tool and material will generate friction during cutting, generating very high pressure and resistance, forming a large amount of heat. This makes the bottom of the chip, the prop, and the bottom reach the heat level, which can melt a substance produced at the melting point of the material being cut and cannot be immediately cut off, This blood combines to take away, forming a very hard complex called a cutting tumor.

It is not combined and cannot be taken away by iron filings. This substance will adhere to the surface of the workpiece and the surface of the cutting tool. Why is the iron blood surface of the initial processing not visible, but is it prone to scratching during precision processing? Because the temperature during processing varies over time.