Magnetic Characterization of CarTech® Hypocore™ Alloy at Cryogenic Temperatures
Continued development of superior soft-magnetic alloys has resulted in improved efficiencies in key technologies, viz., electric motors, generators, transformers, etc. In this work, we present the magnetic properties of a low-cobalt content, soft-magnetic alloy—CarTech® Hypocore™ Alloy—at cryogenic temperatures, that has a unique combination of low coercivity and a high electrical resistivity at ambient temperature. Specimens were cut from the cold-rolled strips (thickness ~130 μm). The X-ray diffraction spectrum revealed the presence of α-phase (bcc solid solution of iron), at 300 K. Magnetic characterization from 60 to 300 K was performed on annealed specimens. The saturation magnetization decreased from ~221 Am2/kg (at 60 K) to ~216 Am2/kg (at 300 K), while the intrinsic coercivity varied between ~220 and ~230 A/m in that temperature regime. The magnetic saturation at 0 K and the magnetic moment per atom for the alloy were estimated as ~221.2 Am2/kg and ~2.17 μB, respectively. The observed soft-magnetic behavior of the alloy at cryogenic temperatures was compared with the other soft-magnetic alloys.
KeywordsCarTech® Hypocore™ Alloy Intrinsic coercivity Saturation magnetization Cryogenic temperatures
The authors would like to thank the College of Engineering and Computer Science at the University of Michigan in Dearborn for the financial (Grant# U049150) and the infrastructural support to conduct the experimental work and Carpenter Technology Corporation for providing the CarTech® Hypocore™ Alloy specimens for the study.
- 5.Cullity BD, Graham CD (2009) Introduction to magnetic materials. IEEE Press, Wiley, HobokenGoogle Scholar
- 6.Fingers RT, Coate JE, Dowling RE (1997) Mechanical properties of iron-cobalt alloys for power applications. Proc Intersoc Energy Convers Eng Conf 1:563Google Scholar
- 7.Moosbrugger C (2000) ASM ready reference: electrical and magnetic properties of metals. ASM International Materials Park, OhioGoogle Scholar
- 9.Carpenter Technical Fact Sheet—CarTech® Hypocore™ Alloy (2016) Copyright 2016 CRS Holdings Inc. (a subsidiary of Carpenter Technology Corporation). https://www.cartech.com/globalassets/literature-files/cartech-hypocore-fact-sheet
- 10.Carpenter Technical Data Sheet—CarTech® Hypocore™ Alloy (2017) Copyright 2017 CRS Holdings Inc. (a subsidiary of Carpenter Technology Corporation). https://www.cartech.com/en/product-solutions/cartech-hypocore-alloy/
- 11.Ruoff C (2017) New motor materials. Charg Electr Veh Mag 30:38–43. https://www.cartech.com/globalassets/literature-files/chargedevs-mag-iss-30—carpenter-hypocore.pdf
- 12.Meka VM, Jayaraman TV, Fitterling EM (2017) Effect of temperature on the magnetic properties of CarTech® Hypocore™ Alloy. IEEE Magn Let 8:5108604Google Scholar
- 18.Nishizawa T, Ishida K (1990) Binary alloy phase diagrams, vol 2 (TB Massalski, ed). ASM International, Metal Park, OhioGoogle Scholar
- 19.Kittel C (2004) Introduction to solid state physics. WileyGoogle Scholar
- 21.Zavaritskii NV, Tsarev VA (1963) Variation of the saturation magnetization of ferromagnetic substances at helium temperatures. Sov Phys JETP 16(5):1154–1158Google Scholar