Magnetic properties of Cu–Mn–Al alloys with shape memory effect

Although Heusler alloys have been known for more than a century, but since the last decade there has been a quantum jump in research in this area. Heusler alloys show remarkable properties, such as ferromagnetic shape memory effect, magnetocaloric effect, half metallicity, and most recently it has been shown that it can be used for direct conversion of heat into electricity. Heusler alloys Ni-Mn-Z (Z=Ga, Al, In, Sn, Sb), show a reversible martensitic transformation and unusual magnetic properties. Other classes of intermetallic Heusler alloy families that are half metallic (such as the half Heusler alloys Ni-Mn-Sb and the full Heusler alloy Co2MnGe) are attractive because of their high Curie temperature and structural similarity to binary semiconductors. Unlike Ni-Mn-Ga, Ni-Mn-In and Ni-Mn-Sn transform from ferromagnetic austenite to non-ferromagnetic martensite. As is consistent with the Clausius-Clapeyron equation, the martensitic phase transformation can be manipulated by a magnetic field, leading to possible applications of these materials enabling the magnetic shape memory effect, energy conversion and solid state refrigeration. In this paper, we summarize the salient features of Heusler alloys, like the structure, magnetic properties and potential application of this family of alloys in industry.

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On the Crossing of β1′ Martensite Crystals Associated with the Reversible Shape Memory Effect in Cu-Zn-Al Alloys

Journal of the Japan Institute of Metals and Materials ◽

10.2320/jinstmet1952.44.8_846 ◽

1980 ◽

Vol 44 (8) ◽

pp. 846-852 ◽

Cited By ~ 6

Author(s):

Kazuyoshi Takezawa ◽

Kenji Adachi ◽

Shin’ichi Sato

Keyword(s):

Shape Memory ◽

Shape Memory Effect ◽

Memory Effect ◽

Al Alloys

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Shape memory effect and magnetic properties of Co-Fe ferromagnetic shape memory alloys

10.1117/12.780089 ◽

2007 ◽

Author(s):

Yunqing Ma ◽

Shuiyuan Yang ◽

Yuxia Deng ◽

Cuiping Wang ◽

Xingjun Liu

Keyword(s):

Magnetic Properties ◽

Shape Memory Alloys ◽

Shape Memory ◽

Shape Memory Effect ◽

Memory Effect ◽

Ferromagnetic Shape Memory Alloys ◽

Ferromagnetic Shape Memory

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NiMn-Based Metamagnetic Shape Memory Alloys

Materials Science Forum ◽

10.4028/www.scientific.net/msf.635.23 ◽

2009 ◽

Vol 635 ◽

pp. 23-31 ◽

Cited By ~ 14

Author(s):

Ryosuke Kainuma ◽

K. Ito ◽

W. Ito ◽

R.Y. Umetsu ◽

T. Kanomata ◽

...

Keyword(s):

Magnetic Properties ◽

Powder Metallurgy ◽

Shape Memory ◽

Shape Memory Effect ◽

Memory Effect ◽

Parent Phase ◽

Martensite Phase ◽

Ternary Alloys ◽

Plasma Sintering ◽

Spark Plasma

The magnetic properties of the parent and martensite phases of the Ni2Mn1+xSn1-x and Ni2Mn1+xIn1-x ternary alloys and the magnetic field-induced shape memory effect obtained in NiCoMnIn alloys are reviewed, and our recent work on powder metallurgy performed for NiCoMnSn alloys is also introduced. The concentration dependence of the total magnetic moment for the parent phase in the NiMnSn alloys is very different from that in the NiMnIn alloys, and the magnetic properties of the martensite phase with low magnetization in both NiMnSn and NiMnIn alloys has been confirmed by Mössbauer examination as being paramagnetic, but not antiferromagnetic. The ductility of NiCoMnSn alloys is drastically improved by powder metallurgy using the spark plasma sintering technique, and a certain degree of metamagnetic shape memory effect has been confirmed.

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