Magnetic shape memory alloys are ferromagnetic materials that generate force and motion under moderate magnetic fields. The typically single crystalline alloys made from nickel, manganese and gallium are able to generate 6% strain under external loads. And they do this with frequencies into the low kilohertz range.
Magnetic Shape Memory Alloy
(Ni50/Mn28/Ga22)
Electrical Properties
Electrical resistivity ( µOhmcm ) 70
Temperature coefficient ( K-1 ) 0.003
Magnetic Properties
Coercivity (Hc) ( A m-1 ) 4000
Curie temperature ( C ) 95 - 105
Initial permeability 2
Maximum permeability 90
Remanence from saturation (Brem) ( T ) 0.02
Saturation flux density ( T ) 0.6
Mechanical Properties
Hardness - Vickers ( kgf mm-2 ) 130
Modulus of elasticity ( GPa ) 8 - 20
Physical Properties
Density ( g cm-3 ) 8
Melting point ( C ) 1130
Thermal Properties
Crystallization temperature ( C ) 1090
Maximum use temperature in air ( C ) 45
Temperature - Austenitic ( C ) 50
Temperature - Martensitic ( C ) 45