skip to main content

DOE PAGESDOE PAGES

This content will become publicly available on March 26, 2019

Title: Effects of Al content and annealing on the phases formation, lattice parameters, and magnetization of A l x F e 2 B 2 ( x = 1.0 , 1.1 , 1.2 ) alloys

AlFe 2B 2 is a ferromagnet with the Curie temperature around 300 K and has the potential to be an outstanding rare-earth free candidate for magnetocaloric applications. However, samples prepared from the melt contain additional phases which affect the functional response of the AlFe 2B 2 phase. Here, we report on the effects of Al content in samples with the initial (nominal) composition of Al xFe 2B 2 where x=1.0, 1.1, and 1.2 prepared by arc-melting followed by suction casting and annealing. The as-cast Al xFe 2B 2 alloys contain AlFe 2B 2 as well as additional phases including the primary solidifying FeB and Al 13Fe 4 compounds which are ferromagnetic and paramagnetic, respectively, at 300 K. The presence of these phases makes it difficult to extract the intrinsic magnetic properties of AlFe 2B 2 phase. Annealing of Al xFe 2B 2 alloys at 1040°C for 3 days allows for reaction of the FeB with Al 13Fe 4 to form the AlFe 2B 2 phase, significantly reduces the amount of additional phases, and results in nearly pure AlFe 2B2 phase as confirmed with XRD, magnetization, scanning electron microscopy, and electronic transport. The values of the magnetization, effective magnetic moment permore » Fe atom, specific heat capacity, electrical resistivity and Seebeck coefficient for the AlFe 2B 2 compound have been established.« less
Authors:
 [1] ;  [2] ;  [3] ;  [3] ;  [2] ;  [4] ;  [5] ;  [3]
  1. Ames Lab., Ames, IA (United States). Division of Materials Sciences and Engineering; Iowa State Univ., Ames, IA (United States). Dept. of Physics and Astronomy
  2. Ames Lab., Ames, IA (United States). Division of Materials Sciences and Engineering
  3. Northeastern Univ., Boston, MA (United States). Dept. of Mechanical Engineering
  4. McCallum Consulting LLC, Santa Fe, NM (United States)
  5. Ames Lab., Ames, IA (United States). Division of Materials Sciences and Engineering; Iowa State Univ., Ames, IA (United States). Dept. of Materials Sciences and Engineering
Publication Date:
Grant/Contract Number:
AR0000754; AC02-07CH11358
Type:
Accepted Manuscript
Journal Name:
Physical Review Materials
Additional Journal Information:
Journal Volume: 2; Journal Issue: 3; Journal ID: ISSN 2475-9953
Publisher:
American Physical Society (APS)
Research Org:
Ames Lab., and Iowa State Univ., Ames, IA (United States); Northeastern Univ., Boston, MA (United States)
Sponsoring Org:
USDOE Advanced Research Projects Agency - Energy (ARPA-E)
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; 75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; AlxFe2B2 alloys; suction casting; annealing; XRD; lattice parameters; SEM; EDS; DSC; magnetization; heat capacity; electrical resistivity; Seebeck coefficient
OSTI Identifier:
1431221
Alternate Identifier(s):
OSTI ID: 1429563