TY - JOUR
T1 - Functional stability of a ferromagnetic polycrystalline Ni2MnGa high temperature shape memory alloy
AU - Azeem, M.A.
AU - Jones, N.G.
AU - Raghunathan, S.L.
AU - Vorontsov, V.A.
AU - Dye, D.
PY - 2017/3/15
Y1 - 2017/3/15
N2 - Electrocaloric Ni2MnGa is of interest for solid state refrigeration applications, as well as a high temperature thermal shape memory alloy. Here, polycrystalline Ni54Mn25Ga21 is examined using in situ synchrotron X-ray diffraction. The initial martensite (Mf) and austenite (Af) finish temperatures were found to be 232 ° C and 298 ° C respectively. Mf was observed to decline by 8 ° C/cycle and Af increased by 1 ° C/cycle. Both below and surprisingly, above the Curie temperature, the application of an e.m.f. was found to affect the lattice parameters measured. A change in the thermal expansion of the two phases was found around the Curie temperature.
AB - Electrocaloric Ni2MnGa is of interest for solid state refrigeration applications, as well as a high temperature thermal shape memory alloy. Here, polycrystalline Ni54Mn25Ga21 is examined using in situ synchrotron X-ray diffraction. The initial martensite (Mf) and austenite (Af) finish temperatures were found to be 232 ° C and 298 ° C respectively. Mf was observed to decline by 8 ° C/cycle and Af increased by 1 ° C/cycle. Both below and surprisingly, above the Curie temperature, the application of an e.m.f. was found to affect the lattice parameters measured. A change in the thermal expansion of the two phases was found around the Curie temperature.
KW - ferromagnetic shape memory alloy
KW - intermetallic compounds
KW - synchrotron radiation
KW - thermal expansion
UR - http://www.scopus.com/inward/record.url?scp=85007453975&partnerID=8YFLogxK
UR - https://spiral.imperial.ac.uk/handle/10044/1/43117
U2 - 10.1016/j.scriptamat.2016.12.012
DO - 10.1016/j.scriptamat.2016.12.012
M3 - Article
AN - SCOPUS:85007453975
SN - 1359-6462
VL - 130
SP - 274
EP - 277
JO - Scripta Materialia
JF - Scripta Materialia
ER -