What is Cutting: Definition and 128 Discussions

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 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 compressive and shearing phenomenon, and occurs only when the total stress generated by the cutting implement exceeds the ultimate strength of the material of the object being cut. The simplest applicable equation is:





stress

=



force


area





{\displaystyle {\text{stress}}={{\text{force}} \over {\text{area}}}}
or



τ
=


F
A




{\displaystyle \tau ={\frac {F}{A}}}

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. 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.

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  1. martijn_tholen

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  2. abdulbadii

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  3. F

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  4. DaveC426913

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  5. J

    B Why are serrated knives more effective than normal knives?

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  6. Luke2642

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  7. H

    B Blunt force vs cutting force in penetration

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  8. B

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  9. russ_watters

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  10. vivek_salman

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  11. E

    Why have a feed force in the cutting process?

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  12. ramadhankd

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  13. Z

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  14. B

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  15. S

    I Adhesive force between cutting oil and metal chips?

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  16. barryj

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  17. jra12222

    B Force at which a cutting disk comes off from an angle grinder

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  18. Julio

    B Problem about a cone and plane cutting it

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  19. Eclair_de_XII

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  20. M

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  21. E

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  22. wolram

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  23. A

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  24. A

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  25. Sveral

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  26. Sveral

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  27. D

    MHB Wood cutting problem

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  28. J

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  29. Dirk

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  30. George Zucas

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  31. RedDelicious

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  32. A

    I Matter cutting by destabilising of atoms bonding

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  33. Ali Durrani

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  34. E

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  35. nicholas0211510

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  36. T

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  37. I

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  38. physicsquestion

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  39. R

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  40. DaveC426913

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  41. D

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  42. C

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  43. G

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  44. MarkFL

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  45. D

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  46. L

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  47. Entanglement

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  48. M

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  50. E

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