Editing Cutting

{{Short description|Partial or complete separation of a body or system into two or more parts}}
{{Other uses}}
[[File:Scissors.jpg|right|frame|Different types of [[scissors]] – sewing (left), paper (middle), kitchen (right)]]
[[File:Glass cutter.jpg|thumb|upright=1.35|A [[glass cutter]], showing hardened steel cutting wheel (far left), notches for snapping, and ball (on end of handle) for tapping]]
'''Cutting''' is the separation or opening of a physical object, into two or more portions, through the application of an acutely directed [[force]].

Implements commonly used for [[wikt:cut|cutting]] are the [[knife]] and [[saw]], or in medicine and science the [[scalpel]] and [[microtome]]. However, any sufficiently sharp object is capable of cutting if it has a [[hardness]] sufficiently larger than the object being cut, and if it is applied with sufficient force. Even liquids can be used to cut things when applied with sufficient force (see [[water jet cutter]]).

Cutting is a [[compression (physical)|compressive]] and [[shearing (physics)|shearing]] phenomenon, and occurs only when the total [[stress (physics)|stress]] generated by the cutting implement exceeds the ultimate [[Strength of materials|strength]] of the material of the object being cut. The simplest applicable equation is:

:<math>\text{stress} = {\text{force} \over \text{area}}</math>   or   <math>\tau=\frac{F}{A}</math>

The stress generated by a cutting implement is directly proportional to the force with which it is applied, and inversely proportional to the area of contact.<ref>{{cite web|url = http://www.freestudy.co.uk/mech%20prin%20h2/stress.pdf|title = Basic Studies Of Stress And Strain|access-date = 5 February 2016|website = www.freestudy.co.uk|url-status = live|archive-url = https://web.archive.org/web/20161213020537/http://www.freestudy.co.uk/mech%20prin%20h2/stress.pdf|archive-date = 13 December 2016}}</ref> Hence, the smaller the area (i.e., the sharper the cutting implement), the less force is needed to cut something. It is generally seen that cutting edges are thinner for cutting soft materials and thicker for harder materials. This progression is seen from [[kitchen knife]], to cleaver, to axe, and is a balance between the easy cutting action of a thin [[blade]] vs strength and edge durability of a thicker blade.

==Metal cutting==
{{more|Cutting (metalworking)}}
Cutting has been at the core of manufacturing throughout history. For metals many methods are used and can be grouped by the physical phenomenon used. It is the process of producing a work piece by removing unwanted material from a block of metal, in the form of chips.
* [[Chip formation|Chip forming]] (material removal processes) – [[sawing]], [[drilling]], [[Milling (machining)|milling]], [[turning]] etc.
* [[Shearing (manufacturing)|Shearing]] – [[punching]], [[Stamping press|stamping]], scissoring, blanking
* [[Abrasion (mechanical)|Abrasive material removal]] – [[Grinding (abrasive cutting)|grinding]], [[lapping]], [[Polishing (metalworking)|polishing]], [[Water jet cutter|water-jet]]
* Heat – [[flame cutting]], [[plasma cutting]], [[laser cutting]]
* Electrochemical – [[etching]], [[electrical discharge machining]] (EDM), [[electrochemical machining]] (ECM)

Every method has its limitations in accuracy, cost, and effect on the material. For example, heat may damage the quality of heat treated alloys, and laser cutting is less suitable for highly reflective materials such as aluminum.<ref>{{cite web|title = FAQ: What are the problems with laser cutting of aluminium and how do I overcome them?|url = http://www.twi-global.com/technical-knowledge/faqs/material-faqs/faq-what-are-the-problems-with-laser-cutting-of-aluminium-and-how-do-i-overcome-them/|website = www.twi-global.com|access-date = 2016-02-05|url-status = dead|archive-url = https://web.archive.org/web/20160121042508/http://www.twi-global.com/technical-knowledge/faqs/material-faqs/faq-what-are-the-problems-with-laser-cutting-of-aluminium-and-how-do-i-overcome-them/|archive-date = 2016-01-21}}</ref> Laser cutting sheet metal produces flat parts and etches and engraves parts from complex or simple designs. It is used over other cutting options for its quick process and customizable abilities.<ref>{{cite web|title = Laser Etching & Cutting Services |url = http://www.hplstampings.com/laser-cutting-etching/|website = HPL Stampings|access-date = 2016-02-05|language = en-US|url-status = live|archive-url = https://web.archive.org/web/20160325235509/http://www.hplstampings.com/laser-cutting-etching/|archive-date = 2016-03-25}}</ref>

==See also==
* [[Tearing]]
* [[Machining]]
* [[Knife sharpening]]
* [[Laser cutting]]
* [[Sharpness (cutting)]]
* [[Water jet cutter|Water jet cutting]]

==References==
{{Reflist}}

==External links==
* {{cite journal|doi=10.1016/j.engfracmech.2006.06.006|title=Optimum blade configurations for the cutting of soft solids|journal=Engineering Fracture Mechanics|volume=73|issue=16|pages=2523–2531|year=2006|last1=Atkins|first1=Tony}}
* [http://home.howstuffworks.com/handsaws.htm How stuff works – Handsaws]
* [http://www.precisionmicro.com/110/photo-etching/photo-etching-vs--traditional-metal-machining Etching vs. traditional metal machining]

{{Cutting and abrasive tools}}
{{Authority control}}

[[Category:Cutting| ]]
[[Category:Suicide methods]]

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