Abstract
An experiment was carried out to investigate the magnetic and physical properties of Sm3(Fe0.81Co0.10V0.09)29Nr and Sms(Fe0.75Co0.10Cr0.15)29Ny compounds. These compounds were prepared by nitrogenation of Sn (Fe0.81Co0.10V0.09)29 and Sm3(Fe0.75Co0.10Cr0.15)29 alloy powders (about 30μm) in high-purity nitrogen gas at pressure of 4.9MPa, and temperatures of 475-600°C for 0.5-5h. Sm3(Fe0.75Co0.10Cr0.15)29Ny alloy powders get a high coerrivily after nitrogenation. It was found when Sm3(Fe0.75Co0.10Cr0.15)29Nr powders were subsequently heated at 500-600°C for 3-25h under 98kPa of argon atmosphere, the value of coercivity of this compounds increased. The conditions determined as optimum for preparing the powders with best values of σs=139.5×10-6Wb-rndkg, HcJ=332kA/m, HA= 4.62MA/m, and Tc = 563.9t, are as follows: nitrogenation ; 600°C×1h, heat treatment ; 5501×10h. These powders were found to absorb approximately 7-8atoms of nitrogen per unit formula.
