The Experts below are selected from a list of 48 Experts worldwide ranked by ideXlab platform

H E Karaca - One of the best experts on this subject based on the ideXlab platform.

  • Magnetic field induced phase transformation in nimncoin Magnetic shape memory alloys a new actuation mechanism with large Work output
    Advanced Functional Materials, 2009
    Co-Authors: H E Karaca, I Karaman, B Basaran, Yang Ren, Y I Chumlyakov, H J Maier
    Abstract:

    Magnetic shape memory alloys (MSMAs) have recently been developed into a new class of functional materials that are capable of Magnetic-field-induced actuation, mechanical sensing, Magnetic refrigeration, and energy harvesting. In the present Work, the Magnetic field-induced martensitic phase transformation (FIPT) in Ni{sub 45}Mn{sub 36.5}Co{sub 5}In{sub 13.5} MSMA single crystals is characterized as a new actuation mechanism with potential to result in ultra-high actuation Work outputs. The effects of the applied Magnetic field on the transformation temperatures, magnetization, and superelastic response are investigated. The Magnetic Work output of NiMnCoIn alloys is determined to be more than 1 MJ m{sup -3} per Tesla, which is one order of magnitude higher than that of the most well-known MSMAs, i.e., NiMnGa alloys. In addition, the Work output of NiMnCoIn alloys is orientation independent, potentially surpassing the need for single crystals, and not limited by a saturation Magnetic field, as opposed to NiMnGa MSMAs. Experimental and theoretical transformation strains and magnetostress levels are determined as a function of crystal orientation. It is found that [111]-oriented crystals can demonstrate a magnetostress level of 140 MPa T{sup -1} with 1.2% axial strain under compression. These field-induced stress and strain levels are significantly higher than those from existingmore » piezoelectric and magnetostrictive actuators. A thermodynamical frameWork is introduced to comprehend the Magnetic energy contributions during FIPT. The present Work reveals that the Magnetic FIPT mechanism is promising for Magnetic actuation applications and provides new opportunities for applications requiring high actuation Work-outputs with relatively large actuation frequencies. One potential issue is the requirement for relatively high critical Magnetic fields and field intervals (1.5-3 T) for the onset of FIPT and for reversible FIPT, respectively.« less

G Kostorz - One of the best experts on this subject based on the ideXlab platform.

  • a microscopic approach to the Magnetic field induced deformation of martensite magnetoplasticity
    Journal of Magnetism and Magnetic Materials, 2003
    Co-Authors: Peter Müllner, Valerevna Anastasija Chernenko, G Kostorz
    Abstract:

    Abstract Deformation experiments were performed in uniaxial compression with a Ni–Mn–Ga single crystal subjected to a Magnetic field perpendicular to the stress axis. Depending on the field strength, different stress–strain curves for loading and unloading were obtained. The Magnetic-field-induced stress (magneto-stress) and the Work done by the corresponding Magnetic force were evaluated. In order to understand the relationship between the magneto-mechanical properties and the microstructure, the microscopic processes occurring during Magnetic-field-induced deformation are discussed in detail. It turns out that the Magnetic Work per unit volume and, to some extent, the macroscopic magneto-stress depend on the microstructure, i.e. the spatial distribution of martensite domains. The Magnetic threshold field required for triggering magnetoplasticity depends on the twin thickness and is controlled by the mutual interaction of twinning dislocations and their interaction with interfaces. The threshold field can be entirely described within this microscopic approach, taking into account the elementary carrier of magnetoplasticity, which is the twinning dislocation.

H J Maier - One of the best experts on this subject based on the ideXlab platform.

  • Magnetic field induced phase transformation in nimncoin Magnetic shape memory alloys a new actuation mechanism with large Work output
    Advanced Functional Materials, 2009
    Co-Authors: H E Karaca, I Karaman, B Basaran, Yang Ren, Y I Chumlyakov, H J Maier
    Abstract:

    Magnetic shape memory alloys (MSMAs) have recently been developed into a new class of functional materials that are capable of Magnetic-field-induced actuation, mechanical sensing, Magnetic refrigeration, and energy harvesting. In the present Work, the Magnetic field-induced martensitic phase transformation (FIPT) in Ni{sub 45}Mn{sub 36.5}Co{sub 5}In{sub 13.5} MSMA single crystals is characterized as a new actuation mechanism with potential to result in ultra-high actuation Work outputs. The effects of the applied Magnetic field on the transformation temperatures, magnetization, and superelastic response are investigated. The Magnetic Work output of NiMnCoIn alloys is determined to be more than 1 MJ m{sup -3} per Tesla, which is one order of magnitude higher than that of the most well-known MSMAs, i.e., NiMnGa alloys. In addition, the Work output of NiMnCoIn alloys is orientation independent, potentially surpassing the need for single crystals, and not limited by a saturation Magnetic field, as opposed to NiMnGa MSMAs. Experimental and theoretical transformation strains and magnetostress levels are determined as a function of crystal orientation. It is found that [111]-oriented crystals can demonstrate a magnetostress level of 140 MPa T{sup -1} with 1.2% axial strain under compression. These field-induced stress and strain levels are significantly higher than those from existingmore » piezoelectric and magnetostrictive actuators. A thermodynamical frameWork is introduced to comprehend the Magnetic energy contributions during FIPT. The present Work reveals that the Magnetic FIPT mechanism is promising for Magnetic actuation applications and provides new opportunities for applications requiring high actuation Work-outputs with relatively large actuation frequencies. One potential issue is the requirement for relatively high critical Magnetic fields and field intervals (1.5-3 T) for the onset of FIPT and for reversible FIPT, respectively.« less

Marlene Kramer - One of the best experts on this subject based on the ideXlab platform.

Claudia Schmalenberg - One of the best experts on this subject based on the ideXlab platform.