What is the function of coolant in enhancing surface finish during milling?

The function of coolant in enhancing surface finish during milling primarily involves maintaining lower temperatures in the cutting zone. When milling, the friction between the cutter and the workpiece generates heat, which can lead to thermal deformation of both the cutter and the workpiece material. This heat can adversely affect the surface finish by causing warping, altering material properties, and leading to tool wear.

By utilizing a coolant, the temperature is kept within a manageable range, which helps in preserving the integrity of both the tool and the workpiece. Cooler temperatures result in reduced thermal expansion and better dimensional stability, allowing for more precise cutting. Additionally, maintaining lower temperatures reduces the likelihood of tool wear and prolongs tool life, both of which contribute to achieving a smoother surface finish.

Using coolant also promotes better lubrication during the cutting process, which enhances the quality of the cut and further contributes to improved surface integrity. Therefore, the primary role of coolant in this context is to manage heat effectively, ensuring optimal cutting conditions and a higher quality surface finish.