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Encyclopedia > Cold rolling
Rolling mill for cold rolling metal sheet like this piece of brass sheet.
Rolling mill for cold rolling metal sheet like this piece of brass sheet.

Cold rolling is a metal working process in which metal is deformed by passing it through rollers at a temperature below its recrystallization temperature. Cold rolling increases the yield strength and hardness of a metal by introducing defects into the metal's crystal structure. These defects prevent further slip and can reduce the grain size of the metal, resulting in Hall-Petch hardening. Image File history File linksMetadata Size of this preview: 450 × 599 pixels Full resolution (480 × 639 pixel, file size: 56 KB, MIME type: image/jpeg) File links The following pages on the English Wikipedia link to this file (pages on other projects are not listed): Cold rolling Metadata This file... Image File history File linksMetadata Size of this preview: 450 × 599 pixels Full resolution (480 × 639 pixel, file size: 56 KB, MIME type: image/jpeg) File links The following pages on the English Wikipedia link to this file (pages on other projects are not listed): Cold rolling Metadata This file... Metalworking is the craft and practice of working with metals to create parts or structures. ... Insulin crystals Recrystallization is an essentially physical process that has meanings in chemistry, metallurgy and geology. ...


Cold rolling is most often used to decrease the thickness of plate and sheet metal.

Contents

Physical metallurgy of cold rolling

Cold rolling is a method of cold working a metal. When a metal is cold worked, microscopic defects are nucleated through out the deformed area. These defects can be either point defects (a vacancy on the crystal lattice) or a line defect (an extra half plane of atoms jammed in a crystal). As defects accumulate through deformation, it becomes increasingly more difficult for slip, or the movement of defects, to occur. This results in a hardening of the metal. Cold Work is a quality imparted on a material as a result of plastic deformation. ... Schematic view on slip mechanism Slip is the process by which plastic deformation is produced by a dislocation motion. ...


If enough line defects accumulate, a grain may split into two or more grains in order to minimize the strain energy of the system. When large grains split into smaller grains, the alloy hardens as a result of the Hall-Petch relationship. If cold work is continued, the hardened metal may fracture. A crystallite is a domain of solid-state matter that has the same structure as a single crystal. ... The Hall-Petch relationship or Hall-Petch Law is a relation in materials science that deals with the connection between the grain size, or crystallite size, and the yield point of a material. ...


During cold rolling, metal absorbs a great deal of energy, some of this energy is used to nucleate and move defects (and subsequently deform the metal). The remainder of the energy is released as heat.


A metal that has been hardened by cold rolling can be softened by annealing. Annealing will relieve stresses, allow grain growth, and restore the original properties of the alloy. After anealing, the metal my be further cold rolled with out fracturing. Annealing, in metallurgy and materials science, is a heat treatment wherein a material is altered, causing changes in its properties such as strength and hardness. ...


Degree of cold work

Cold rolled metal is given a rating based on the degree it was cold worked. "Skin-rolled" metal undergoes the least rolling, being compressed only 0.5-1% to harden the surface of the metal and make it more easily workable for later processes. Higher ratings are "quarter hard," "half hard" and "full hard"; in the last of these, the thickness of the metal is reduced by 50%.

The ridges and top edge of this can were formed by cold rolling.

Image File history File linksMetadata Download high-resolution version (601x800, 65 KB) Can of Sapporo beer. ... Image File history File linksMetadata Download high-resolution version (601x800, 65 KB) Can of Sapporo beer. ...

Cold rolling as a manufacturing process

Cold rolling is a common manufacturing process. It is often used to form sheet metal. Beverage cans are closed by rolling, and steel food cans are strengthened by rolling ribs into their sides. Rolling mills are commonly used to precisely reduce the thickness of strip and sheet metals.



Metalworking:

Metal forming: Image File history File links Blacksmith-hammer-anvil-50x50. ... Turned chess pieces Metalworking is the craft and practice of working with metals to create structures or machine parts. ...

Coin die | Coining | Cold rolling | Die | Drawing | Electromagnetic forming | Flypress | Hot rolling | Hydraulic press | Hydroforming | Machine press | Progressive stamping | Progressive die | Punching | Punch press | Rolling | Shear | Sinking | Stamping press | Metal spinning | Swage A coin die is one of the two metallic pieces that are used to strike one side of a coin. ... Coining is a form of precision stamping. ... A die is a tool used in the manufacturing industry to create a wide variety of products and components. ... Drawing is a manufacturing process for producing a wire, bar or tube by pulling on a material until it increases in length. ... A pinched aluminium can, produced from a pulsed magnetic field created by rapidly discharging 2 kilojoules from a high voltage capacitor bank into a 3-turn coil of heavy gauge wire. ... A Flypress is a metalworking machine tool used to punch holes in sheet metal in one operation, rather than by cutting the hole or drilling, etc. ... Hot rolling is a metallurgical process in which the metal is passed through a pair of rolls and the temperature of the metal is above its recrystallization temperature, as opposed to cold rolling, which takes place below it. ... Hydraulic force increase. ... Hydroforming (or hydramolding) is a cost-effective way of shaping malleable metals such as aluminum into lightweight, structurally stiff and strong pieces. ... Power press with a fixed barrier guard A press, or a machine press is a tool used to work metal (typically steel) by changing its shape and internal structure. ... Progressive (punch and blanking) die with strip and punchings Progressive stamping is a metalworking method that can encompass punching, coining, bending and several other ways of modifying metal raw material, combined with an automatic feeding system. ... Progressive die with strip and punchings A progressive stamping die (die) is a metalworking device that is designed and built to convert a strip of metal raw material into parts that to conform blueprint specifications. ... Metals Punching in metal fabrication is the process of using a machine to press a shape through a sheet of metal and into a die to create that shape in the metal. ... A Punch Press is a machine that has a set of punches and dies, a male (punch) and female (die), which when pressed together put a hole into the material used that is the same geometry as the punch that is being used. ... profile rolling (to manufacture a cone) Rolling is a fabricating process in which the metal, plastic, paper, glass, etc. ... A guillotine is a machine used to accurately cut sheet metal. ... Location within China Changchun (Simplified Chinese: 长春; Traditional Chinese: 長春; pinyin: ; Wade-Giles: Chang-chun) is the capital of the Jilin province in northeastern China. ... A stamping press (press) is a manufacturing device that is designed and built to operate progressive stamping dies and other types of dies. ... Metal Spinning is a process by which circles of metal are shaped over mandrels (also called forms) while mounted on a spinning lathe by the application of levered force with various tools. ... Swaging is a metal forming technique in which the metal is plastically deformed to its final shape using high pressures. ...


Metalworking topics:   Turned chess pieces Metalworking is the craft and practice of working with metals to create structures or machine parts. ...

Casting | CNC | Cutting tools | Drilling and threading | Fabrication | Finishing | Grinding | Jewellery | Lathe (tool) | Machining | Machine tooling | Measuring | Metalworking | Hand tools | Metallurgy | Milling | Occupations | Press tools | Smithing | Terminology | Welding Casting may be used to create artistic sculptures Casting is a manufacturing process by which a molten material such as metal or plastic is introduced into a mold, allowed to solidify within the mold, and then ejected or broken out to make a fabricated part. ... A CNC Turning Center A CNC Milling Machine The abbreviation CNC stands for computer numerical control, and refers specifically to a computer controller that reads G-code instructions and drives the machine tool, a powered mechanical device typically used to fabricate metal components by the selective removal of metal. ... a Cutting Tool, in the context of Metalworking is any tool that is used to remove metal from the workpiece by means of shear deformation. ... Drilling is the process of using a drill bit in a drill to produce holes. ... A typical steel fabrication shop Fabrication, when used chas an industrial term, applies to the building of machines and structures by cutting, shaping and assembling components made from raw materials. ... Metalworking finishing is the activity of making things out of metal in a skillful manner. ... Rotating abrasive wheel on a bench grinder. ... Amber jewellery in the form of pendants Jewellery (also spelled jewelry, see spelling differences) is a personal ornament, such as a necklace, ring, or bracelet, made from jewels, precious metals or other substance. ... Conventional metalworking lathe In woodturning, metalworking, metal spinning, and glassworking, a lathe is a machine tool which spins a block of material so that when abrasive, cutting, or deformation tools are applied to the block, it can be shaped to produce an object which has rotational symmetry about an axis... A lathe is a common tool used in machining. ... A machine tool is a powered mechanical device, typically used to fabricate metal components of machines by the selective removal of metal. ... The examples and perspective in this article or section may not represent a worldwide view. ... Turned chess pieces Metalworking is the craft and practice of working with metals to create structures or machine parts. ... Metalworking hand tools are hand tools that are used in the metalworking field. ... A Blacksmith, the father of the modern metallurgist. ... Endmills for a milling machine. ... It has been suggested that this article or section be merged with Smith (metalwork). ... Power press with a fixed barrier guard A press, or a machine press is a tool used to work metal (typically steel) by changing its shape and internal structure. ... A smith, or metalsmith, is a person involved in the shaping of metal objects. ... This article needs to be wikified. ... Welding is a fabrication process that joins materials, usually metals or thermoplastics, by causing coalescence. ...

References

Reed-Hill, Robert, Et. Al. "Physical Metallurgy Principles", 3rd Edition, PWS publishing, Boston, 1991. ISBN 978-0534921736.


  Results from FactBites:
 
Method for producing cold rolled titanium strips - Patent 4398406 (2394 words)
The cold rolling of a titanium strip is carried out under the conditions represented by the following formula: X.ltoreq.(48673/Y.sup.1.3283) where X is an average grain size (.mu.m) of the pre-cold rolled titanium strip and Y is a diameter (mm) of the roll for the cold rolling.
Characteristics of the pickup in the cold rolling of titanium strips are such that in the rolling process, titanium, upon solidification, firmly sticks on the surface of the roll and that once the pickup has started, it markedly increases in subsequent rolling.
A commercially pure titanium strip as hot rolled of 2.8 mm thick (grain size: from 1 to 2 micrometers), as the pre-cold rolled strip, was cold rolled to 1.0 mm thick at a rolling speed of 54 m/min.
  More results at FactBites »


 
 

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