A dislocation model for the magnetic field induced shape memory effect in Ni2MnGa
نویسندگان
چکیده
The magnetically driven shape memory effect in Ni2MnGa body-centered tetragonal martensite is onset by the motion of 0.144 h1 1 1i type twin dislocations on the {1 1 2} type planes. Calculations show that the application of a 400 kA/m magnetic field can induce a shear stress of approximately 2.8 MPa on these twin dislocations, a value exceeding the Peierls and the yield stress for Ni2MnGa. 2005 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.
منابع مشابه
Experimental Study on the Magnetomechanical Characteristics of Ni-Mn-Ga Ferromagnetic Shape Memory Alloy Single Crystals
Magnetic shape memory properties of Ni-Mn-Ga single crystals were characterized by measurement of stress-induced martensite reorientation under constant magnetic fields. Also magnetic field-induced strain as a function of the applied magnetic field under different constant compressive stress levels has been investigated. All the experiments were performed at room temperature in which the sample...
متن کاملMagneto-Structural Properties of Ni2MnGa Ferromagnetic Shape Memory Alloy in Magnetic Fields
The purpose of this review was to investigate the correlation between magnetism and crystallographic structures as it relates to the martensite transformation of Ni2MnGa type alloys, which undergo martensite transformation below the Curie temperature. In particular, this paper focused on the physical properties in magnetic fields. Recent researches show that the martensite starting temperature ...
متن کاملExchange Bias and Inverse Magnetocaloric Effect in Co and Mn Co-Doped Ni2MnGa Shape Memory Alloy
Exchange bias effect observed in the Ni1.68Co0.32Mn1.20Ga0.80 alloy confirms the coexistence of antiferromagnetic and ferromagnetic phases in the martensite phase. A large inverse magnetocaloric effect has been observed within the martensitic transformation temperature range, which is originated from modified magnetic order through magnetic-field-induced phase transformation from partially anti...
متن کاملNovel Research for Development of Shape Memory Alloys
Shape memory alloys have attracted much attention due to their attractive properties for applications as well as their basic aspects of deformation and transformation in structural and magnetic behavior. In 1951, the Au–Cd alloy was discovered [1]. After that, numberless shape memory alloys have been developed. A lot of applications of shape memory alloys were realized after the Ti–Ni alloy was...
متن کاملاثر میدان مغناطیسی 5/7 میلیتسلا کوتاه مدت بر یادگیری فضایی موش
Background & Aim: In human environment, magnetic fields are created by electrical generators, power lines, and electrical instruments. These fields could affect learning and memory. This study was planned to evaluate whether short time exposure to magnetic fields has any significant effect on spatial memory. Material & Method: In this experimental study, we used 10 male Albino Wistar mice ...
متن کامل