http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
Nd - Fe - B계 소결자석의 자기적특성 향상 연구
김윤배(Yoon B. Kim),정우상(W.S. Jung),정원용(W.Y. Jeung) 한국자기학회 2002 韓國磁氣學會誌 Vol.12 No.2
In order to increase the magnetic properties of a Nd-Fe-B sintered magnet, the general factors including particle size and its distribution, volume fraction of Nd₂Fe₁₄B phase, degree of alignment of Nd₂Fe₁₄B grain, oxygen content and grain size etc. should be optimized by controlling the composition of Nd-Fe-B alloy as well as the manufacturing process. In this study, fabrication of the Nd-Fe-B sintered magnet was carried out in a laboratory scale by controlling the composition of Nd-Fe-B alloy and the manufacturing process. The optimum milling condition was found by investigating the milling media, milling time and ball size. The addition of FeGa was effective to increase the coercivity of the Nd-Fe-B sintered magnet. A remanence of 14.4 kG, a coercivity of 9.4 kOe and a maximum energy product of 47 MGOe were obtained from the sintered magnet.
Al-Li계 합금에 있어서δ' 상의 조대화 현상에 미치는 Cu 와 MG 의 영향
신명철,박중근,김제덕,정우상 대한금속재료학회(대한금속학회) 1993 대한금속·재료학회지 Vol.31 No.8
The coarsening behavior of δ′(AI₃Li) phase has been studied in various alloys of Al-Li, Al-Li-Cu and Al-Li-Cu-Mg systems using transmission electron microscopy. The coarsening kinetics are well governed by Ostwald ripening theory in all cases. The ccarsening rate depends sensitively on the volume fraction of δ′ phase particulary in binary system, which conforms relatively well to the MLSW theory. The addition of Cu in Al-Li binary alloy ○ds to accelerate the coarsening rate of δ′ phase. This is believed to be due to the variation of δ′ interfacial energy. The addition of Mg in Al-Li-Cu ternary alloy tends to reduce the δ′ coarsening rate. This is because the precipitation of S′ phase has an effect to reduce the diffusivity of Li atom by depleting the concentration of vacancy.