Skip to Main Content
 

Global Search Box

 
 
 
 

ETD Abstract Container

Abstract Header

EFFECT OF ANNEALING ON THE MICROSTRUCTURE AND MAGNETIC PROPERITES OF SELECTED (Ni-Mn-Ga) MELT-SPUN RIBBONS

Abstract Details

2016, Master of Science, Miami University, Physics.
A series of bulk and nanostructured ribbons of intermetallic alloys based on Ni-Mn-Ga have been fabricated and characterized. The samples have been fabricated by arc melting and melt spinning techniques and investigated by x-ray diffraction, scanning electron microscopy, and magnetization measurements. The as spun ribbons are amorphous but transforms to tetragonal D022 structure after annealing. While the annealed bulk samples and the as spun ribbons exhibit no ferromagnetism, the ribbons annealed under various thermal conditions are found to be ferromagnetic. For the Ni0.2Mn3.2Ga0.6 ribbons annealed at 450 °C for 30 minutes a large coercive field of about 2528 Oe, have been observed. The SEM images show that no grain forms on the as spun ribbons prepared at wheel speed of 57 m/s. However, the formation of the nano-grains is observed in the annealed Ni0.2Mn3.2Ga0.6 ribbons. The ribbons annealed at 450 °C for 30 minutes has grain size around 70 nm. The results of the experimental study show that the microstructure and the associated magnetic properties of the materials can be strongly controlled by annealing techniques. The coercive field and the shape of the magnetic hysteresis loops vary significantly with the annealing conditions. The experimental results suggest that the Ni- Mn-Ga based materials may have strong potential for permanent magnet applications.
Mahmud Khan (Advisor)
Herbert Jaeger (Committee Member)
Khalid Eid (Committee Member)

Recommended Citations

Citations

  • Alshammari, O. (2016). EFFECT OF ANNEALING ON THE MICROSTRUCTURE AND MAGNETIC PROPERITES OF SELECTED (Ni-Mn-Ga) MELT-SPUN RIBBONS [Master's thesis, Miami University]. OhioLINK Electronic Theses and Dissertations Center. http://rave.ohiolink.edu/etdc/view?acc_num=miami1464184585

    APA Style (7th edition)

  • Alshammari, Ohud. EFFECT OF ANNEALING ON THE MICROSTRUCTURE AND MAGNETIC PROPERITES OF SELECTED (Ni-Mn-Ga) MELT-SPUN RIBBONS. 2016. Miami University, Master's thesis. OhioLINK Electronic Theses and Dissertations Center, http://rave.ohiolink.edu/etdc/view?acc_num=miami1464184585.

    MLA Style (8th edition)

  • Alshammari, Ohud. "EFFECT OF ANNEALING ON THE MICROSTRUCTURE AND MAGNETIC PROPERITES OF SELECTED (Ni-Mn-Ga) MELT-SPUN RIBBONS." Master's thesis, Miami University, 2016. http://rave.ohiolink.edu/etdc/view?acc_num=miami1464184585

    Chicago Manual of Style (17th edition)