Editing Cutting fluid (section)

=== Cooling ===
Metal cutting  generates [[heat]] due to friction and energy lost deforming the material.<ref>{{Cite journal |last=Abukhshim |first=N. A. |last2=Mativenga |first2=P. T. |last3=Sheikh |first3=M. A. |date=2006-06-01 |title=Heat generation and temperature prediction in metal cutting: A review and implications for high speed machining |url=https://www.sciencedirect.com/science/article/abs/pii/S089069550500180X |journal=International Journal of Machine Tools and Manufacture |volume=46 |issue=7 |pages=782–800 |doi=10.1016/j.ijmachtools.2005.07.024 |issn=0890-6955|url-access=subscription }}</ref> The surrounding air has low [[thermal conductivity]] (conducts heat poorly) meaning it is a poor coolant.<ref>{{cite journal |last1=Tai |first1=Bruce L. |last2=Dasch |first2=Jean M. |last3=Shih |first3=Albert J. |title=Evaluation and comparison of lubricant properties in minimum quantity lubrication machining |journal=Machining Science and Technology |date=October 2011 |volume=15 |issue=4 |pages=376–391 |doi=10.1080/10910344.2011.620910 }}</ref> Ambient air cooling is sometimes adequate for light cuts and low duty cycles typical of [[maintenance, repair and operations]] (MRO) or hobbyist work. Production work requires heavy cutting over long time periods and typically produces more heat than air cooling can remove. Rather than pausing production while the tool cools, using liquid coolant removes significantly more heat more rapidly, and can also speed cutting and reduce friction and tool wear.

However, it is not just the tool which heats up but also the work surface. Excessive temperature in the tool or work surface can ruin the [[Tempering (metallurgy)|temper]] of both, soften either to the point of uselessness or failure, burn adjacent material, create unwanted [[thermal expansion]] or lead to unwanted chemical reactions such as [[oxidation]].

Regulating the heat created during machining processes is necessary to extend tool life, prevent the alteration of the workpieces heat treatment, and prevent warping of the piece.<ref>{{Citation |last=Abdelbary |first=Ahmed |title=Introduction to engineering tribology |date=2023 |work=Principles of Engineering Tribology |pages=1–32 |url=https://www.sciencedirect.com/topics/materials-science/cutting-fluid#:~:text=Main%20purposes%20of%20cutting%20fluids,and%20reduces%20cutting%20tool%20wear. |access-date=2025-04-14 |publisher=Elsevier |language=en |doi=10.1016/B978-0-323-99115-5.00013-X |isbn=978-0-323-99115-5 |last2=Chang |first2=Li|url-access=subscription }}</ref> The use of cutting fluids allows machinists to cut faster than they would be capable of if relying on surrounding air to cool the workpiece.