• 한국재료학회지
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• 제12권3호
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• pp.220-224
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• 2002

The oxide scales formed on $Ni_3Al$-7.8%Cr-1.3%Zr-0.8%Mo-0.025%B after oxidation at 900, 1000 and 110$0^{\circ}C$ in air were studied using XRD, SEM, EPMA and TEM. The oxide scales consisted primarily of $NiO,\; NiAl_2O_4,\;{\alpha}-Al_2O_3,\; monoclinic-ZrO_2,\; and \;tetragonal-ZrO_2$. The outer layer of the oxide scale was rich in Ni-oxides, whereas the internal oxide stringers were rich in Al-oxides and $ZrO_2$. Within the above oxide scales, Cr and Mo tended to exist as dissolved ions.

• 공업화학
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• 제7권5호
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• pp.1006-1014
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• 1996

에틸렌 이량화반응을 위한 일련의 $NiO-ZrO_2/WO_3$촉매를 염화니켈-옥시염화 질코니움 수용액을 공침시키고 ammonium metatungstate용액으로 함침시킨 다음 공기 중에서 소성하여 제조하였다. X-선 회절과 DSC로부터 얻은 결과를 근거로 하면 $ZrO_2$에 NiO 및 $WO_3$를 첨가하면 $ZrO_2$와 첨가된 산화물과의 상호작용으로 $ZrO_2$의 무정형에서 tetragonal phase로의 상전이 온도가 더 높은 온도로 이동되었다. $WO_3$가 첨가되지 않은 $NiO-ZrO_2$는 에틸렌 이량화반응에 전혀 촉매 활성을 나타내지 아니하였으나 $WO_3$가 첨가된 $NiO-ZrO_2/WO_3$촉매는 실온에서도 높은 활성을 나타내었다. 이와 같은 $NiO-ZrO_2/WO_3$의 높은 촉매활성은 $WO_3$의 유도효과에 의한 산세기의 증가와 밀접한 관련이 있었다.

• 한국추진공학회:학술대회논문집
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• 한국추진공학회 2009년도 제33회 추계학술대회논문집
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• pp.421-425
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• 2009

재생냉각형 액체로켓 연소기 챔버에서 열차폐 코팅이 미치는 열/구조적인 영향에 대하여 유한요소 해석을 통하여 고찰하였다. 열차폐 코팅은 현재 개발하고 있는 연소기에 사용되는 NiCrAlY-$ZrO_2$과 향후 적용할 가능성이 있는 Ni-Cr 두 종류를 적용하였다. 열/구조해석 결과 NiCrAlY-$ZrO_2$ 코팅이 Ni-Cr 코팅에 비하여 열차폐에 의한 온도감소 효과가 크게 나타났다. 결과적으로 냉각채널의 온도와 변형 또한 NiCrAlY-$ZrO_2$ 코팅을 적용하였을 때 Ni-Cr 코팅보다 감소하였다. 외측구조물의 구조안정성에 있어서 Ni-Cr 코팅이 미치는 영향은 없었으나, NiCrAlY-$ZrO_2$ 코팅은 외측구조물의 유효응력을 감소시켜 챔버의 구조안정성을 증가시켰다.

• 한국재료학회지
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• 제12권8호
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• pp.617-623
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• 2002

In order to improve the hydrogen storage capacity and the activation properties of the hydrogen storage alloys, the rare-earth metal alloy series, $MmNi_{ 4.5}$$Mn_{0.5}$ $Zr_{x}$ (x=0, 0.025, 0.05, 0.1), are prepared by adding the excess Zr in $MmNi_{4.5}$ $Mn_{0.5}$ / alloy for the strong resistance to intrinsic degradation. The hydrogen storage alloys of rare-earth metal such as $LaNi_{5}$ , and $MmNi_{5}$X and $MmNi_{4.5}$ /$_Mn{0.5}$ alloys which substituted La by misch metal properties were characterized as well. The hydrogen storage alloys were produced by melting each metal mixture in arc melting furnace, and the as-cast alloys were heat-treated at $1100^{\circ}C$ for 10 hr. The major elements of misch metal(Mm) were La, Ce, Pr and Nd with some impurities less than 1wt.% determined by ICP-AES. X-ray diffraction indicated that the structure for these samples was a single phase of hexagonal with $CaCu^{5}$ type. As the Zr contents increases, the activation time and the plateau pressure decrease and sloping of the plateau pressure increase. Amount of the 2nd phases increases with increase in Zr contents in $MmNi_{ 4.5}$$Mn_{0.5}$ $Zr_{0.1}$ alloy, This phenomenon indicated that $ZrNi_3$ in this phase, which shows the maximum storage capacity and the strong resistance to intrinsic degradation, is considered as a proper alloy for hydrogen storage..

• 한국진공학회:학술대회논문집
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• 한국진공학회 1994년도 제6회 학술발표회 논문개요집
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• pp.35-35
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• 1994

The surface segragation of NiZr, CuZr alloy has been studied wi th X-ray Imotoelectron spectroscopy(XPS), Auger electron spectroscopy(AES) and low energy ion scattering(LEIS). The composition of outmost atomic layer has been determinded by the use of LEIS at several incident energies using Ar+ ion. In the LEIS analysis, the effect of charge exchange has been estimated by a novel measurment of the charge exchange parameters while simul taneous determining the relative concentrations of Ni and Zr and the complementary information obtained will be described. The composition of the clean annealed surface, measured with AES only, will be contrasted wi th the surface concentration of the preferentially sputtered surface. The experimental results has been clearly demonstrated that when the NiZr ruld CuZr alloys are exposed to continuous Ar+ ion bombardment the outermost atomic layer is Zr rich due to preferential sputtering of Ni atoms. where Ni is preferentially sputtered, but the difference in sputtering yields is not sufficient to explain the observed composition. Therefore, it is necessary to consider other processes such as Radiation Induced Segregation(RIS). The surface composition of the heated sample surface predicts that Zr should surface segregate which futher supports the view that part of the Zr enrichment is due to RIS.to RIS.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2000년도 영호남학술대회 논문집
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• pp.246-249
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• 2000

The effects of Zr on the mechanical workability and tensile strength of Cu-Ni-Mn-Sn-Al alloys have been investigated and the following results were obtained. The mechanical workability of Cu-Ni-Mn-Sn-Al alloys are increased with addition of Zr. And the surface cracks of specimen were not produced in Zr added Alloys. Especially in condition of hot-worked beyond the 90% working ratio, Zr contained specimen showed intra-granule crack propagation but Zr-free specimen showed inter-granule mode. The tensile strength have maximum value in 0.05% Zr contained alloy. The aging mechanism of Cu-Ni-Mn-Sn-Al alloys were varied by Zr addition.

• 한국수소및신에너지학회논문집
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• 제8권2호
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• pp.51-56
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• 1997

Laves상 $ZrV_2$합금은 다량의 수소를 저장하지만 수소와의 결합력이 강하여 Ni-MH전지의 전극으로는 부적당하다. 전극에 응용하기 위해 $ZrV_2$합금중의 V의 일부를 Ni로 치환하여 수소와의 결합력을 약하게 하였다. 이와 같은 Zr-V-Ni계 합금에 대해 전기화학적 성질, 전극의 평형전위로부터 합금중의 수소의 열역학적성질 및 2차전지전극에의 응용가능성을 조사하였다.

• 한국재료학회지
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• 제15권12호
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• pp.765-772
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• 2005

PAS(Plasma Activated Sintering) process was tried to apply for the fabrication of BMG(Bulk Metallic Glasses) of $Ni_{57}Zr_{20}Ti_{18}Si_5}\;and\;Ni_{57}Zr_{20}Ti_{18}Si_3Sn_2$ from the as-atomized amorphous powder. Compressive strength for the BMG(bulk Metallic Glasses) of $Ni_{57}Zr_{20}Ti_{18}Si_5$ were lower than those of BMG rods produced by warm extrusion ,or copper mold casting method. Microstructural examination by optical microcope, SEM ana EDS showed that oxidation had occurred during PASintering. In order to prevent the powder from the oxidation during PASintering, Ni coating for $Ni_{57}Zr_{20}Ti_{18}Si_5$ amorphous powder by electroless-plating method was performed. Microstructural examination for Ni coated layers after PASintering indicated that the Ni coating had been so effective to prevent powder from oxidation during PASintering. Sintering behaviors of $Ni_{57}Zr_{20}Ti_{18}Si_3Sn_2$ represent the same as those of $Ni_{57}Zr_{20}Ti_{18}Si_5$.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2007년도 추계학술대회 논문집
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• pp.72-72
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• 2007

Ni 단일박막과 Ni-Zr 합금박막을 단결정 Si 기판위에 증착한 후 RTP를 이용하여 Ni 실리사이드 형성반응을 관찰하였고, $500^{\circ}C$에서 형성된 Ni 실리사이드 박막에 $600^{\circ}C,\;650^{\circ}C$에서 후속 열처리 공정을 수행하여 열 안정성을 평가하였다. RTP를 이용하여 실리사이드를 형성할 경우, Ni/Si 계의 경우, 고온 열처리에서 $NiSi_2$ 결정립의 과대 성장 및 단락이 발생하였지만, Ni-Zr/Si 계의 경우 첨가된 내열금속 원소가 NiSi에서 $NiSi_2$ 로의 상전이와 핵생성을 지연시켜 Ni 실리사이드 박막의 열 안정성 개선 효과를 확인하였다.

• 한국재료학회지
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• 제12권8호
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• pp.624-633
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• 2002

In order to improve the hydrogen storage capacity and the activation properties of the hydrogen storage alloys, the rare-earth metal alloy series, MmN $i_{4.5}$M $n_{0.5}$Z $r_{x}$(x=0, 0.025, 0.05, 0.1), are prepared by adding excess Zr in MmN $i_{4.5}$M $n_{0.5}$ alloy. The various parts in hydrogen storage vessel consisted of copper pipes reached the setting temperature within 4~5 minutes after heat addition, which indicated that storage vessel had a good heat conductivity required in application. The performance test on storage vessel filled with rare-earth metal alloys of 1000 gr was also conducted after hydrogen charging for 10 min at $18^{\circ}C$ under 10 atm. It showed that the average capacity of discharged hydrogen volume was found to be for $MmNi_{4.5}$ $Mn_{0.5}$ and $MmNi_{4.5}$ $Mn_{x}$ 0.5/$Zr_{samples}$ indicated that the released amount of hydrogen for this $AB_{5}$ type alloys was more than 92 % of theoretic value, and also it was found that the optimum discharging temperature for obtaining an appropriate pressure of 3 atm was determined to be $V^{\circ}C$ for $MmNi_{4.5}$ $Mn_{0.5}$$Zr_{x}$(x=0, 0.025, 0.05, 0.1) hydrogen storage alloys. The released amount of these hydrogen storage samples was 125 $\ell$ , 122.4 $\ell$ and 108.15 $\ell$/kg for $MmNi_{4.5}$ $Mn_{0.5}$ $Zr_{0.025}$ $MmNi_{4.5}$M $n_{0.5}$Z $r_{0.05}$, and MmN $i_{4.5}$ Mn_0.5$Zr_{0}$, at $70^{\circ}C$ respectively. Amount of the 2nd phases increase with increase on Zr contents in $MmNi_{4.5}$$Mn_{0.5}$ $Zr_{ 0.1}$/ alloy. This phenomenon indicates that$ ZrNi_3$ in $MmNi_{4.5}$ $Mn_{0.5}$ $Zr_{x}$ / phase, which shows the maximum storage capacity and the strong resistance to intrinsic degradation, is considered as a proper alloy for hydrogen storage. As the Zr contents increase, the activation time and the plateau pressure decreases and sloping of the plateau pressure increases.creases.eases.s.