• 한국세라믹학회지
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• 제26권3호
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• pp.323-330
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• 1989

Wear restance titanium carbonitride (TiCN) films were deposited on the SKH9 tool steels and WC-Co cutting tools by plasma assisted chemical vapor deposition (PACVD) using a gaseous mixture of TiCl4, CH4, N2, H2 and Ar. The effects of the deposition temperature and RF(Radio Frequency) power on the deposition rate, chlorine content and crystallinity of the deposited layer were studied. The experimental results showed that the stable and adherent films could be obtained above the deposition temperature of 47$0^{\circ}C$ and maximum deposition rate was obtained at 485$^{\circ}C$. The deposition rate was much affected by RF power and maximum at 40W. The crystallinity of the deposited layer was improved with increasing the deposition temperature and RF power. The TiCN films deposited by PACVD contained much chlorine. The chlorine content in the TiCN films was affected by deposition conditions and decreased with improving the crystallinity of the deposited layer. The deposited TiCN films deposited at the deposition temperature of 52$0^{\circ}C$ and RF power of 40W had an uniform surface with very fine grains of about 500$\AA$ size. The microhardness of the deposited layer was 2,300Kg/$\textrm{mm}^2$.

• Asian Journal of Atmospheric Environment
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• 제11권4호
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• pp.270-282
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• 2017

To evaluate the deposition amount on a ground surface, mesoscale numerical models coupled with atmospheric chemistry are widely used for larger horizontal domains ranging from a few to several hundreds of kilometers; however, these models are rarely applied to high-resolution simulations. In this study, the performance of a dry and wet deposition model is investigated to estimate the amount of deposition via computational fluid dynamics (CFD) models with high grid resolution. Reynolds-averaged Navier-Stokes (RANS) simulations are implemented for a cone and a two-dimensional ridge to estimate the dry deposition rate, and a constant deposition velocity is used to obtain the dry deposition flux. The results show that the dry deposition rate of RANS generally corresponds to that observed in wind-tunnel experiments. For the wet deposition model, the transport equation of a new scalar concentration scavenged by rain droplets is developed and used instead of the scalar concentration scavenged by raindrops falling to the ground surface just below the scavenging point, which is normally used in mesoscale numerical models. A sensitivity analysis of the proposed wet deposition procedure is implemented. The result indicates the applicability of RANS for high-resolution grids considering the effect of terrains on the wet deposition.

• 한국정보전자통신기술학회논문지
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• 제14권2호
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• pp.122-127
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• 2021

본 논문은 ITO 유리를 기판으로 사용하여 CdS 박막을 제작하였다. MDS (Multiplex Deposition Sputter System)을 이용하여 RF power와 증착시간을 변화시키면서 소자를 제작하였다. 제작된 시편은 광학적 특성에 대해 분석을 하였다. 본 논문의 목적은 태양전지의 광흡수층에 적용될 수 있는 제작조건을 찾는 것이다. RF power가 50W이고 증착 시간이 10분 일 때, 두께는 64Å로 측정되었다. 100W일?, 두께는 406Å로 측정되었고, 150W일 때는 두꼐는 889Å로 측정되었다. 박막은 RF power가 증가할수록 두께가 증가되는 것을 확인하였다. 광투과율 측정한 결과, 550~850nm는 RF power가 50W, 100W, 150W일 때 모두 투과율이 대략 70% 이상으로 관찰되었다. RF power가 증가되면 두께가 증가되고 입자 크기가 커지므로 박막의 밀도가 증가되어 광투과율이 감소되었다. RF power를 100W로 하고 증착시간을 15분 일 때, 밴드갭은 3.998eV로 계산되었다. 증착시간을 20분일 때, 3.987eV이고 150W는 15분에서는 3.965eV이며 20분에서는 3.831eV이다. RF power가 증가하면 밴드갭이 증가하는 것으로 측정되었다. XRD 분석에서 RF power와 증착시간의 변화에 관계없이 2Θ=26.44에서의 회절 피크를 관찰할 수가 있었다. 반치폭은 증착시간이 증가하면 감소되는 것을 알 수가 있었다. 그리고 RF power를 일정하게 하고 증착시간을 증가하면 입자크기는 증가되는 것으로 측정되었다.

• 열처리공학회지
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• 제3권1호
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• pp.1-7
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• 1990

To investigate the influence of r.f. power and electrode distance on the TiN deposition, TiN films were deposited onto STC3, STD11 steel and Si-wafer from gas mixtures of $TiC_4/N_2/H_2$ using the radio frequency plasma assisted chemical vapor deposition. The crystallinity of TiN film could be improved by the increase of r.f. power and the decrease of electrode distance. The TiN coated layer contains chlorine, its content were decreased with increasing r.f. power as well as decreasing electrode distance. And the thickness of deposited TiN was largely affected by r.f. power and electrode distance. The hardness of deposited TiN reached a maximum value of about Hv 2,000.

• 동력기계공학회지
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• 제18권5호
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• pp.94-99
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• 2014

In this study, AISI M2 powder was selected primarily through various literature in order to improve the hardness and wear resistance. Among the laser metal deposition parameters, laser power was studied to improve the deposition efficiency in the laser metal deposition using a diode pumped disk laser. SKD61 hot work steel plate and AISI M2 powder were used as a substrate and powder for laser metal deposition, respectively. Fixed parameters are CTWD, focal position, travel speed, powder feed rate, etc. Experiments for the laser metal deposition were carried out by changing laser power. Through optical micrographs analysis of cross-section in LMD track, effect of the major parameters were predicted by track pitch. As the track pitch increased, so the reheated zone width, the overlap width and the minimum thickness was decreased. The hardness was decreased in the HAZ area, the hardness in the reheated HAZ area was decreased significantly and regularly in particular.

• 한국기계가공학회지
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• 제20권6호
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• pp.59-69
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• 2021

Directed energy deposition (DED) is an additive manufacturing technology involving a focused high-power laser or electron beam propagating over the substrate, resulting in melt pool formation while simultaneously supplying metal powder to the melt pool area to deposit the material. DED is performed to repair and strengthen parts in various applications, as it can be easily integrate local area cladding and cross-material deposition. In this study, we characterize stainless steel 316 L parts fabricated via DED based on various deposition conditions and geometries to widen the application of DED. The deposition characteristics are investigated by varying the laser power and powder feed rate. Multilayer deposition with a laser power of 362 W and a powder feed rate of 6.61 g/min indicate a height closest to the design value while affording high surface quality. The microhardness of the specimen increases from the top to the bottom of the deposited area. Tensile tests of specimens with two different deposition directions indicate that horizontally long specimens with respect to a substrate demonstrate a higher ultimate tensile strength and yield strength than vertically long specimens with lower elongation.

• 한국전기전자재료학회논문지
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• 제22권8호
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• pp.671-676
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• 2009

The $Sr_{0.7}Bi_{2.3}Nb_2O_9$(SBN) thin films are deposited on Pt-coated electrode(Pt/Ti/$SiO_2$/Si) using RF sputtering method at various deposition conditions. We investigated the effect of deposition condition on the surface morphology and dielectric properties of SBN thin films. The optimum of the rougness showed about 4.33 nm in 70/30 of Ar/$O_2$ ratio. The crystallinity and rougness of SBN thin films were increased with the increase of rf power. Also, Deposition rate of SBN thin films was about 4.17 nm/min in 70 W of rf power. The capacitance of SBN thin films were increased with the increase of Ar/$O_2$ ratio, rf power and deposition temperature respectively.

• 소성∙가공
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• 제24권4호
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• pp.272-279
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• 2015

The characteristics of the laser metal deposition parameters were studied to enhance the deposition efficiency using a diode pumped disk laser. STD61 hot tool steel plate and Fe based AISI M2 alloy were used as a substrate and powder for the laser metal deposition, respectively. Among the laser metal deposition parameters the laser power, track pitch and powder feed rate were used to estimate the deposition efficiency. From the experimental results, the deposition efficiency was shown to be excellent when 1.8kW laser power 500um track pitch and 10g/min of the powder feed rate were used. For this optimal condition the average hardness of the deposition track was approximately 830HV, and this value is 30~50% better than the hardness of the commercially produced tool steel after heat treatment.

• 한국자기학회지
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• 제12권6호
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• pp.224-230
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• 2002

직경 200mm의 실리콘 기판에 균일한 코발트 금속박막을 증착하는 DC-스퍼터 장비에서 공정변수는 증착온도, 증착압력, DC power로 하고 종속변수(response)는 면저항, 면저항 균일도로 하는 '||'&'||'quot;통계적 실험방법'||'&'||'quot;을 채택한 실험을 수행하여 Co 박막의 공정 특성에 대해 다음과 같은 결과를 얻었다 '||'&'||'quot;통계적 실험방법'||'&'||'quot;을 이용한 Co박막의 공정 특성을 조사하는 본 실험에서 면저항과 면저항 균일도는 0.05 이하의 significance수치. 낮은 RMS error, 0.91 이상의 R-sq수치로부터 실험의 우수한 신뢰성을 확인하였다. 면저항에 대한 공정변수의 영향성은 증착온도가 -1.83$\Omega$/$\square$의 감소효과, 증착압럭이 1.17$\Omega$/$\square$의 증가 효과. DC power가 -0.65$\Omega$/$\square$의 감소 효과로 실험 구간에서 일정한 경향의 영향성을 보였으며, 면저항 균일도에서는 증착온도에 의해 $25^{\circ}C$~147$^{\circ}C$에서 -4.04%의 감소로 증착온도에 가장 민감함을 확인하였다. Co 박막의 최적 증착 조건은 증착온도 $25^{\circ}C$, 증착압력 12mTorr, DC power 1500 W로 예상되었다.

• 한국기계가공학회지
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• 제14권3호
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• pp.50-56
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• 2015

In this study, AISI M2 powder was selected primarily through various pieces of literature in order to improve the hardness and wear resistance. Among the laser metal deposition parameters, laser power was studied to improve the deposition efficiency in the laser metal deposition using a diode-pumped disk laser. An SKD61 hot work steel plate and AISI M2 powder were used as a substrate and powder for laser metal deposition, respectively. Experiments for the laser metal deposition were carried out by changing the laser power and track layer. The quality of the track surface and cross-section after applying the single-layer method was better than that obtained from applying the multi-layer method. As the laser power increased, the track thickness was increased, and the surface roughness deviation was decreased. In laser power condition of 1.6kW, the maximum hardness of the deposition track was 790Hv. This value was 40% better than the hardness of the SKD61 after heat treatment.