NdFe10.7Ti1.3의 결정학적 및 자기적 성질 연구

다국어 초록 (Multilingual Abstract)

NdFe_(10.7)Ti_(1.3) has been studied with X-ray diffraction, Mossbauer spectroscopy and vibrating sample magnetometer(VSM). The alloys were prepared by arc-melting under an argon atmosphere. The NdFe_(10.7)Ti_(1.3) contains some α-Fe, from X-ray and Mossbauer measurements. The NdFe_(10.7)Ti_(1.3) has the ThMn₁₂-type tetragonal structure with α_0=8.607 Å and c_0=4.790 Å. The Curie temperature(Tc) of the NdFe_(10.7)Ti_(1.3) is 590 K from Mossbauer spectroscopy performed at various temperatures ranging from 13 to 800 K. Each spectrum below Tc was fitted with six subspectra of Fe sites in the structure(8i₁, 8i₂, 8j₂, 8j₁, 8f and α-Fe). The area fractions of the subspectra at room temperature are 13.8 %, 15.4 %, 17 %, 16.4 %, 34.1 % and 3.3 %, respectively. Magenetic hyperfine fields for the Fe sites decrease in the order, Hhf(8i)＞Hhf(8j)＞Hhf(8f). The abrupt changes in the magnetic hyperfine field, isomer shift and magnetic moment observed at about 180 K in NdFe_(10.7)Ti_(1.3) are attributed to spin reorientation.