The Mn-Zn ferrite powders were prepared by high energy ball milling, then compacted and sintered at various temperatures to assess their sintering behavior and magnetic properties. The initial ferrite powders were spherical in shape with the size of approximately 70 m. After 3 h of ball milling at 300 rpm, aggregated powders ~230 nm in size and composed of ~15 nm nanoparticles were formed. The milled powders had a density of ~70 % when compacted at 490 MPa for 3 min. In the samples subsequently sintered at 1,273 K ~ 1,673 K for 3 h, the MnZnFe2O4 phase was detected. The density of the sintered samples had a tendency to increase with increasing sintering temperature up to 1,473 K, which produced the highest density of 98 %. On the other hand, the sample sintered at 1,373 K had the highest micro-hardness of approximately 610 Hv, which is due to much finer grains.
The annealing characteristics of cold-rolled Al-6.5Mg-1.5Zn-0.5Fe-0.5Mn alloy, newly designed as an automobile material, are investigated in detail, and compared with those of other aluminum alloys. Using multi-pass rolling at room temperature, the ingot aluminum alloy is cut to a thickness of 4 mm, width of 30 mm, and length of 100 mm to reduce the thickness to 1 mm (r = 75 %). Annealing after rolling is performed at various temperatures ranging from 200 to 500 oC for 1 hour. The specimens annealed at temperatures up to 300 oC show a deformation structure; however, from 350 oC they have a recrystallization structure consisting of almost equiaxed grains. The hardness distribution in the thickness direction of the annealed specimens is homogeneous at all annealing temperatures, and their average hardness decreases with increasing annealing temperature. The tensile strength of the as-rolled specimen shows a high value of 496 MPa; however, this value decreases with increasing annealing temperature and becomes 338MPa after annealing at 400 oC. These mechanical properties of the specimens are compared with those of other aluminum alloys, including commercial 5xxx system alloys.
In this paper, a new Co10Fe10Mn35Ni35Zn10 high entropy alloy (HEA) is identified as a strong candidate for the single face-centered cubic (FCC) structure screened using the upgraded TCFE2000 thermodynamic CALPHAD database. The Co10Fe10Mn35Ni35Zn10 HEA is fabricated using the mechanical (MA) procedure and pressure-less sintering method. The Co10Fe10Mn35Ni35Zn10 HEA, which consists of elements with a large difference in melting point and atomic size, is successfully fabricated using powder metallurgy techniques. The MA behavior, microstructure, and mechanical properties of the Co10Fe10Mn35Ni35Zn10 HEA are systematically studied to understand the MA behavior and develop advanced techniques for fabricating HEA products. After MA, a single FCC phase is found. After sintering at 900℃, the microstructure has an FCC single phase with an average grain size of 18 μm. Finally, the Co10Fe10Mn35Ni35Zn10 HEA has a compressive yield strength of 302 MPa.
The effect of adding Ca on the microstructural and mechanical properties of as-cast Mg-11Li-3Zn-1Sn(wt%) alloys were investigated. Mg-11Li-3Zn-1Sn-0.4Mn with different Ca additions (0.4, 0.8, 1.2 wt%) were cast under an SF6 and Co2 atmosphere at 720 oC. The cast billets were homogenized at 400 oC for 12h and extruded at 200 oC. The microstructural and mechanical properties were analyzed by OM, XRD, SEM, and tensile tests. The addition of Ca to the Mg-11Li-3Zn-1Sn-0.4Mn alloy resulted in the formation of Ca2Mg6Zn3, MgSnCa intermetallic compound. By increasing Ca addition, the volume fraction and size of Ca2Mg6Zn3 with needle shape were increased. This Ca2Mg6Zn3 intermetallic compound was elongated to the extrusion direction and refined to fine particles due to severe deformation during hot extrusion. The elongation of the 0.8 wt% Ca containing alloy improved remarkably without reduction strength due to the formation of fine grain and Ca2Mg6Zn3 intermetallic compounds by Ca addition. It is probable that fine and homogeneous Ca2Mg6Zn3 intermetallic compounds played a significant role in the increase of mechanical properties.
[ Zn2(1-x)MnxSiO4 ]0.07≤x≤0.15) green phosphor was prepared by solid state reaction. The first heating was at 900˚C-1250˚C in air for 3 hours and the second heating was at 900˚C in N2/H2(95%/5%) for 2 hours. The size effect of SiO2 in forming Zn2SiO4 was investigated. The temperature for obtaining single phase Zn2SiO4 was lowered from 1100˚C to 1000˚C by decreasing the SiO2 particle size from micro size to submicro size. The effect of the activators for the Photoluminescence (PL) intensity of Zn2SiO4:Mn2+ was also investigated. The PL intensity properties of the phosphors were investigated under vacuum ultraviolet excitation (147 nm). The emission spectrum peak was between 520 nm and 530 nm, which was involved in green emission area. MnCl2·4H2O, the activator source, was more effective in providing high emission intensity than MnCO3. The optimum conditions for the best optical properties of Zn2SiO4:Mn2+ were at x = 0.11 and 1100˚C. In these conditions, the phosphor particle shape was well dispersed spherical and its size was 200 nm.
A study was conducted to determine the effects of the cattle manure (CM) application on the botanical composition and micro-mineral contents (Fe, Mn, Cu, Zn) of grazing pasture at the experimental field of Livestock Division, Subtropical Animal Experiment Station, National Institute of Animal Science from year 2003 to 2005. The experiment was arranged in a randomized complete block design with three replications. The treatment consisted of T1: 100% chemical fertilizer (CF 100%), T2: 50% CF +50% CM, T3: 25% CF +75% CM, T4: 100% cattle manure (CM 100%), T5: 100% CM (1st yr.)+ 100% CF (2nd yr.) + 100% CM (3rd yr.), T6: 100% CM (1st yr.)+ 100% CF (2nd yr.)+ 100% CF (3rd yr.). The botanical composition of grassland for grass, legumes, and weeds showed that the rate of legumes was increased in all treatments. The weeds rate in T4 was the highest in comparison to the other treatments. For micro-mineral contents T5 showed the highest average Fe contents of 262.08 ppm and T1 showed the lowest (199.20 ppm). Mn contents was the highest in T1 among the other treatments. Zn contents was the highest in T3 as compared with other treatments. Cu contents was the highest in T6 as compared with other treatments. The results of this experiments indicated that micro-mineral contents of change was effect of legumes increased than treatment
Ceramic Injection Moulding (CIM) technology has been successfully used for the fabrication of Mn-Zn Ferrite part. The binder was composed by polypropylene and paraffin wax. The optimal powder loading (58% vol.) was determined by means of rheological measurements. Threedifferent parts, toroids, bending and tensile probes were injected. Thermal and solvent-thermal debinding was designed based on DSC and TGA studies of the binder. The time of the debinding cycle was reduced using n-heptane to dissolve previously the paraffin wax. Final properties have been determined and compared with uniaxial pressure parts values. The densities obtained were slightly higher than those of uniaxial pressure parts and the magnetic properties presented similar values.
미량요소 Fe, Mn, Cu 및 Zn의 systematic variation 시비가 orchardgrass 및 white clover의 생육, 개화, 수량, 양분 함량 등에 미치는 영향 등을 구명하였다. 다량요소 양분을 동일량 시비한 조건에서 Fe/Cu(시험군-1), Mn/Zn(시험군-2) 및 Fe+Cu/Mn+Zn(시험군-3) 시험에서는 각 시험군 처리별 총 시비량을 systematic variation 방법으로 0/100, 25/75, 50/50, 7
Orchardgrass 및 white clover에서 미량요소 Fe, Mn, Cu 및 Zn의 systematic variation 시비가 목초의 생육, 개화, 수량, 양분 함량 등에 미치는 영향 등을 구명하였다. 다량요소 양분을 동일량 시비한 조건에서 Fe/Cu(시험군-1), Mn/ Zn(시험군-2) 및 Fe+Cu/Mn+Zn(시험군-3) 시험에서는 systematic variation 방법으로 각 시험군 처리별 총 시비량을 0/100, 25/75, 50
Orchardgrass 및 white clover에서 미량요소 Fe, Mn, Cu 및 Zn의 systematic variation 시비가 목초의 생육, 개화, 수량 및 양분 함량 등에 미치는 영향 등을 구명하였다. 다량요소 양분을 동일량 시비한 조건에서 시험군-1(Fe/Cu), 시험군-2(Mn/Zn), 시험군-3(Fe+Cu/Mn+Zn)의 처리내용은 시험군별 처리양분의 총 시비량()을 systematic variation 방법으로 각각 0/100, 25/
Orchardgrass 및 white clover에서 미량요소 Fe, Mn, Cu 및 Zn의 systematic variation 시비가 목초의 생육, 개화, 수량 및, 양분 함량 등에 미치는 영향 등을 구명하였다. 다량요소 양분을 동일 양 시비한 조건에서 Fe/Cu(시험군-1), Mn/Zn(시험군-2) 및 Fe+Cu/Mn+Zn(시험군-3)의 처리는 systematic variation 방법으로 시험군별 총 시비량을 각각 0/100, 25/75, 50/
Orcharduass 및 white clover에서 미량요소 Fe, Mn, Cu, Zn의 systematic variations 시비가 목초의 생육, 재화, 수량, 양분 함량 등에 미치는 영향 등을 구명하였다. 다량요소 양분을 동일량 시비한 조건에서 시험군-1(Fe/Cu), 시험군-2(Mn/Zn), 시험군-3(Fe+Cu/Mn+Zn)의 처리내용은 시험군별 총 시비량을 systematic variation 방법으로 각각 0/100, 25/75, 50/50,
Orcharduass 및 white clover의 단파 및 혼파재배조건에서 미량요소 Fe, Mn, Cu, Zn, Mo 및 B의 조합시비가 목초의 생육, 개화, 수양, 양분함량 및 식생구성비율 등에 미치는 영향을 구명하였다. 다양요소 양분을 동일량 시비한 조건에서 7 수준의 미량요소 조합시비는 ; 대조구, ; Fe, : Fe+Mn, ; Fe+Mn+Cu, ; Fe+Mn+Cu+Zn, : Fe+Mn+Cu+Zn+Mo 및 ; Fe + Mn +Cu+Zn+Mo + B
Orchardgrass 및 white clover의 단파 및 혼파 재배조건에서 미량요소 Fe, Mn, Cu, Zn, Mo및 B의 조합시비가 목초의 생육, 개화, 수량, 양분 함량 및 식생구성비율 등에 미치는 영향을 구명하였다. 다량요소 양분을 동일 량 시비한 조건에서 7 수준의 미량요소 조합시비는 ;대구조, ; Fe, ; Fe+Mn, : Fe+Mn+Cu, ; Fe+Mn+Cu+Zn, ; Fe+Mn+Cu+Zn+Mo 및 ;Fe+Mn+Cu+Zn+Mo+B로 하였
Orchardgrass 및 white clover의 단파 및 혼파 재배조건에서 미량요소 Fe, Mn, Cu, Zn, Mo및 B의 조합시비가 목초의 생육, 개화, 수량, 양분 함량 및 식생구성비율 등에 미치는 영향을 구명하였다. 다량요소 양분을 동일 량 시비한 조건에서 7 수준의 미량요소 조합시비는 ; 대조구, ; Fe, ; Fe+Mn, ; Fe+Mn+Cu, ; Fe+Mn+Cu+Zn, ; Fe+Mn+Cu+Zn+Mo 및 ; Fe+Mn+Cu+Zn+Mo+B로
Orchardgrass 및 white clover의 단파 및 혼파재배조건에서 미량요소 Fe, Mn, Cu, Zn, Mo 및 B의 조합시비가 목초의 생육, 개화, 수량, 양분 함량 및 식생구성비율 등에 미치는 영향을 구명하였다. 다량료소 양분을 동일 량 시비한 조건에서 7 수준의 미량요소 조합시비는 T; 대조구, T; Fe, T; Fe+Mn, T; Fe+Mn+Cu, T; Fe+Mn+Cu+Zn, T;Fe+Mn+Cu+Zn+Mo 및 T; Fe+Mn+Cu+Zn+