Content deleted Content added
Quisqualis (talk | contribs) →Magnetostrictive hysteresis loop: Copyedit (minor) |
Citation bot (talk | contribs) Removed proxy/dead URL that duplicated identifier. | Use this bot. Report bugs. | Suggested by Abductive | Category:Magnetic ordering | #UCB_Category 20/45 |
||
| (27 intermediate revisions by 21 users not shown) | |||
Line 1:
{{
'''Magnetostriction'''
{{cite journal|title=On the Effects of Magnetism upon the Dimensions of Iron and Steel Bars|journal=The London, Edinburgh, and Dublin Philosophical Magazine and Journal of Science|date=1847|first=J.P.|last=Joule|volume= 30, Third Series|pages=76–87, 225–241|url=https://books.google.com/books?id=VEgEAAAAYAAJ&q=joule%20annals%20electricity%20219%201842&pg=PA76|access-date=2009-07-19 }} Joule observed in this paper that he first reported the measurements in a "conversazione" in Manchester, England, in {{Cite journal
| last = Joule
Line 10:
}}</ref>
Magnetostriction applies to magnetic fields, while [[electrostriction]] applies to electric fields.
== Explanation ==
Internally, ferromagnetic materials have a structure that is divided into ''[[magnetic domain|domains]]'', each of which is a region of uniform magnetization. When a magnetic field is applied, the boundaries between the domains shift and the domains rotate; both of these effects cause a change in the material's dimensions. The reason that a change in the magnetic domains of a material results in a change in the material's dimensions is a consequence of [[magnetocrystalline anisotropy]]
The reciprocal effect, the change of the magnetic susceptibility (response to an applied field) of a material when subjected to a mechanical stress, is called the [[Villari effect]]. Two other effects are related to magnetostriction: the [[Matteucci effect]] is the creation of a helical anisotropy of the susceptibility of a magnetostrictive material when subjected to a [[torque]] and the [[Wiedemann effect]] is the twisting of these materials when a helical magnetic field is applied to them.
The Villari reversal is the change in sign of the magnetostriction of [[iron]] from positive to negative when exposed to magnetic fields of approximately 40 [[Amperes_per_meter|kA/m]].
On magnetization, a magnetic material undergoes changes in volume which are small: of the order 10<sup>−6</sup>.
Line 31 ⟶ 32:
Magnetostrictive materials can convert magnetic energy into [[kinetic energy]], or the reverse, and are used to build [[actuator]]s and [[sensor]]s. The property can be quantified by the magnetostrictive coefficient, λ, which may be positive or negative and is defined as the fractional change in length as the magnetization of the material increases from zero to the [[saturation (magnetic)|saturation]] value. The effect is responsible for the familiar "[[mains hum|electric hum]]" ({{Audio|Mains hum 60 Hz.ogg|Listen}}) which can be heard near [[transformer]]s and high power electrical devices.
Cobalt exhibits the largest room-temperature magnetostriction of a pure element at 60 [[wikt:microstrain|microstrain]]s. Among alloys, the highest known magnetostriction is exhibited by [[Terfenol-D]], (Ter for [[terbium]], Fe for [[iron]], NOL for [[Naval Ordnance Laboratory]], and D for [[dysprosium]]). Terfenol-D, {{
[[File:Magnetostrictive flow sensor.png|thumb|Schematic of a whisker flow sensor developed using thin-sheet magnetostrictive alloys.]]
Another very common magnetostrictive composite is the amorphous alloy {{
Cobalt [[ferrite (magnet)|ferrite]],
In early [[sonar]] transducers
===Mechanical behaviors of magnetostrictive alloys===
====Effect of microstructure on elastic strain alloys====
[[Single crystal|Single-crystal]] alloys exhibit superior microstrain, but are vulnerable to yielding due to the anisotropic mechanical properties of most metals. It has been observed that for [[polycrystalline]] alloys with a high area coverage of preferential grains for microstrain, the mechanical properties ([[ductility]]) of magnetostrictive alloys can be significantly improved. Targeted metallurgical processing steps promote [[abnormal grain growth]] of {011} grains in [[galfenol]] and [[alperm|alfenol]] thin sheets, which contain two easy axes for magnetic domain alignment during magnetostriction. This can be accomplished by adding particles such as [[boride]] species <ref>{{cite journal|last1=Li|first1=J.H.|last2=Gao|first2=X.X.|last3=Xie|first3=J.X.|last4=Yuan|first4=C.|last5=Zhu|first5=J.|last6=Yu|first6=R.B.|date=July 2012|title=Recrystallization behavior and magnetostriction under pre-compressive stress of Fe–Ga–B sheets|journal=Intermetallics|volume=26|pages=66–71|doi= 10.1016/j.intermet.2012.02.019}}</ref> and [[niobium]] carbide ({{
For a polycrystalline alloy, an established formula for the magnetostriction, λ, from known directional microstrain measurements is:<ref>{{cite journal|last1=Grössinger|first1=R.|last2=Turtelli|first2=R. Sato|last3=Mahmood|first3=N.|date=2014|title=Materials with high magnetostriction|journal=IOP Conference Series: Materials Science and Engineering|volume=60|issue=1|pages=012002|doi= 10.1088/1757-899X/60/1/012002|bibcode=2014MS&E...60a2002G|doi-access=free}}</ref>
λ<sub>s</sub> = 1/5(2λ<sub>100</sub>+3λ<sub>111</sub>)
[[File:Tensiletestgallium.png|thumb|Magnetostrictive alloy deformed to fracture
During subsequent [[hot rolling]] and [[Recrystallization (metallurgy)|recrystallization]] steps, particle strengthening occurs in which the particles introduce a “pinning” force at [[grain boundaries]] that hinders normal ([[stochastic]]) grain growth in an annealing step assisted by a {{
====Compressive stress to induce domain alignment====
For actuator applications, maximum rotation of magnetic moments leads to the highest possible magnetostriction output. This can be achieved by processing techniques such as stress annealing and field annealing. However, mechanical pre-stresses can also be applied to thin sheets to induce alignment perpendicular to actuation as long as the stress is below the buckling limit. For example, it has been demonstrated that applied compressive pre-stress of up to ~50 MPa can result in an increase of magnetostriction by ~90%. This is hypothesized to be due to a "jump" in initial alignment of domains perpendicular to applied stress and improved final alignment parallel to applied stress.<ref>
{{cite journal|title=Compressive pre-stress effects on magnetostrictive behaviors of highly textured Galfenol and Alfenol thin sheets|journal=AIP Advances|date=January 2017|first1=J|last1=Downing|first2=S-M|last2=Na|first3=A|last3=Flatau|author3-link=Alison Flatau|volume=7|issue=5|pages=056420|id=056420|doi=10.1063/1.4974064|bibcode=2017AIPA....7e6420D|doi-access=free}}</ref>
These materials generally
==Applications==
▲These materials generally shows non-linear behavior with change in applied magnetic field and stress. For small magnetic field, linear piezomagnetic constitutive<ref>{{Cite book|last=Isaak D|first=Mayergoyz|title=Handbook of giant magnetostrictive materials|publisher=Elsevier|year=1999|isbn=|location=|pages=}}</ref> behavior is enough. Non-linear magnetic behavior is captured using classical macroscopic model such as Preisach model<ref>{{Cite journal|last=Preisach|first=F.|date=May 1935|title=�ber die magnetische Nachwirkung|url=http://link.springer.com/10.1007/BF01349418|journal=Zeitschrift f�r Physik|language=de|volume=94|issue=5–6|pages=277–302|doi=10.1007/BF01349418|s2cid=122409841|issn=1434-6001|via=}}</ref> and Jiles-Atherton model.<ref>{{Cite journal|last1=Jiles|first1=D. C.|last2=Atherton|first2=D. L.|date=1984-03-15|title=Theory of ferromagnetic hysteresis (invited)|url=http://aip.scitation.org/doi/10.1063/1.333582|journal=Journal of Applied Physics|language=en|volume=55|issue=6|pages=2115–2120|doi=10.1063/1.333582|bibcode=1984JAP....55.2115J|issn=0021-8979}}</ref> For capturing magneto-mechanical behavior, Armstrong<ref>{{Cite journal|last=Armstrong|first=William D.|date=1997-04-15|title=Burst magnetostriction in Tb0.3Dy0.7Fe1.9|url=http://aip.scitation.org/doi/10.1063/1.364992|journal=Journal of Applied Physics|language=en|volume=81|issue=8|pages=3548–3554|doi=10.1063/1.364992|bibcode=1997JAP....81.3548A|issn=0021-8979}}</ref> proposed a energy average approach. More recently, Wahi ''et al.''<ref>{{Cite journal|last1=Wahi|first1=Sajan K.|last2=Kumar|first2=Manik|last3=Santapuri|first3=Sushma|last4=Dapino|first4=Marcelo J.|date=2019-06-07|title=Computationally efficient locally linearized constitutive model for magnetostrictive materials|url=http://aip.scitation.org/doi/10.1063/1.5086953|journal=Journal of Applied Physics|language=en|volume=125|issue=21|pages=215108|doi=10.1063/1.5086953|bibcode=2019JAP...125u5108W|issn=0021-8979}}</ref> proposed a computationally efficient constitutive model wherein constitutive behavior is accurately captured using locally linearizing scheme.
* [[Electronic article surveillance#Acousto-magnetic systems|Electronic article surveillance]] – using magnetostriction to prevent [[shoplifting]]▼
* [[Delay-line memory#Magnetostrictive delay lines|Magnetostrictive delay lines]] - an earlier form of computer memory
* Magnetostrictive [[Loudspeaker#Magnetostrictive speakers|loudspeakers]] and [[Headphones#Other transducer technologies|headphones]]
==
* [[Electromagnetically induced acoustic noise and vibration]]
* [[Inverse magnetostrictive effect]]
* [[Wiedemann effect]] – a torsional force caused by magnetostriction
* [[Magnetomechanical effects]] for a collection of similar effects
* [[Magnetocaloric effect]]
Line 72 ⟶ 77:
* [[Piezomagnetism]]
* [[SoundBug]]
* [[FeONIC]]
* [[Terfenol-D]]
* [[Galfenol]]
▲* [[Electronic article surveillance]] – using magnetostriction to prevent [[shoplifting]]
==
{{reflist}}
==
* [http://hyperphysics.phy-astr.gsu.edu/hbase/solids/magstrict.html Magnetostriction]
* {{Cite web
Line 89 ⟶ 93:
}}
* [http://www.feonic.com/technology Invisible Speakers from Feonic that use Magnetostriction]
* [http://rema-cn-e.sxl.cn/ Magnetostrictive alloy maker: REMA-CN] {{Webarchive|url=https://web.archive.org/web/20170321170708/http://rema-cn-e.sxl.cn/ |date=2017-03-21 }}
{{Authority control}}
| |||