Title :
Nitrogen diffusion patterns on RE2Fe17 compounds, RE=Pr, Nd, Sm and Gd
Author :
Colucci, C.C. ; Gama, S. ; Cabral, F.A.O.
Author_Institution :
Inst. de Fisica Glen Wataghin, Univ. Estadual de Campinas, Brazil
fDate :
9/1/1992 12:00:00 AM
Abstract :
The nitrogen diffusion patterns for several RE2Fe176 intermetallic compounds are studied. The nitriding process was done in both slabs and powder samples, which were characterized and analyzed thermomagnetically and metallographically. Thermographic analysis shows two phases: the pure 2:17 and the fully nitrided one for several nitrogen concentrations in all samples studied. Metallographic analyses confirm the presence of two phases. A broadening caused by stress or by dilution was detected for the pure phase transition. The nitriding process occurs by diffusion mechanisms: along preferential paths at low temperature and according to the shell-core model at higher temperatures
Keywords :
Curie temperature; crystal microstructure; diffusion in solids; ferromagnetic properties of substances; gadolinium alloys; iron alloys; magnetic properties of fine particles; metallography; neodymium alloys; nitridation; permanent magnets; powder metallurgy; praseodymium alloys; samarium alloys; 673 K; 773 K; 873 K; Curie temperature; Gd2Fe17Nx; N2 diffusion patterns; Nd2Fe17Nx; Pr2Fe17Nx; Sm2Fe17Nx; diffusion mechanisms; intermetallic compounds; metallographic analysis microstructure; nitriding process; powder; pure phase transition; shell-core model; slabs; thermal magnetic analysis; thermographic analysis; Coils; Copper; Intermetallic; Iron; Magnetic analysis; Neodymium; Nitrogen; Powders; Samarium; Slabs;
Journal_Title :
Magnetics, IEEE Transactions on
