Magnetism and local environment model in (Ni/sub 1-c/Co/sub c/)/sub 0/ /sub 78/P/sub 0/ /sub 14/B/sub 0/ /sub 08/ amorphous alloys

Technical Report · Tue Jun 01 00:00:00 EDT 1976

DOI:https://doi.org/10.2172/7308049· OSTI ID:7308049

Amamou, A.

The magnetic properties of amorphous alloys (Ni/sub 1-c/Co/sub c/)/sub 0/./sub 78/P/sub 0/./sub 14/B/sub 0/./sub 08/ were investigated. The samples were prepared by the splat-cooling method. The Curie temperatures were determined and the magnetization measurements, performed for 1.7/sup 0/K less than or equal to T less than or equal to 270/sup 0/K and fields up to kOe. Ni/sub 0/./sub 78/P/sub 0/./sub 14/B/sub 0/./sub 08/ is paramagnetic, whereas Co/sub 0/./sub 78/P/sub 0/./sub 14/B/sub 0/./sub 08/ is ferromagnetic until the crystallization temperature (678/sup 0/K). The average moment per cobalt atom is 1.15 ..mu../sub B/. In (Ni/sub 1-c/Co/sub c/)/sub 0/./sub 78/P/sub 0/./sub 14/B/sub 0/./sub 08/ the critical concentration for the paramagnetic-ferromagnetic transition is c approximately equal to 0.15; this transition occurs in an inhomogeneous way. The saturation magnetization in the whole concentration range can be interpreted (as for some crystallized alloys and compounds) by a local environment model, when a reasonable short-range order is assumed. In such a model the magnetic moment per cobalt atom is related merely to the number of its Co first neighbors n/sub Co/. For n/sub Co/ = 0 and 1 the cobalt atom is not magnetic, for n/sub Co/ = 2 and 3 it carries a small moment ..mu../sub 1/ = 0.50..mu../sub B/ and for n/sub Co/ greater than 3 it is magnetic with ..mu../sub 2/ = 1.15..mu../sub B/ as in Co/sub 0/./sub 78/P/sub 0/./sub 14/B/sub 0/./sub 08/; the nickel atoms do not carry a substantial moment in the entire concentration range. These features are comparable to those obtained in some crystalline alloys. 3 figures.

• Research Organization: California Inst. of Tech., Pasadena (USA). W.M. Keck Lab. of Engineering Materials
• OSTI ID: 7308049
• Report Number(s): CALT-822-84
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360104* -- Metals & Alloys-- Physical Properties
ALLOY SYSTEMS
ALLOYS
AMORPHOUS STATE
BORON COMPOUNDS
COBALT ALLOYS
COBALT BASE ALLOYS
CURIE POINT
LOW TEMPERATURE
MAGNETIC MOMENTS
MAGNETIC PROPERTIES
MAGNETIZATION
MEDIUM TEMPERATURE
NICKEL ALLOYS
NICKEL BASE ALLOYS
PHASE TRANSFORMATIONS
PHOSPHORUS COMPOUNDS
PHYSICAL PROPERTIES
QUATERNARY ALLOY SYSTEMS
THERMODYNAMIC PROPERTIES
TRANSITION TEMPERATURE
ULTRALOW TEMPERATURE
VERY LOW TEMPERATURE