• Journal of Welding and Joining
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• 제16권6호
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• pp.52-58
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• 1998

The effect of Si content in welding wires on th arc stability was investigate, in the region of short circuit transfer and spray transfer. In the region of short circuit transfer, with increasing Si content, average arcing time and average short circuit time were increased. Therefore, droplet transfer frequency was decreased, due to the increase of arcing time and peak current at the moment of arc-reiginition was increased, due to the increase of short circuit time. In the region of spray transfer, the fluctuations of arc current and arc voltage was the most stable in wire with Si content of about 00.60 wt.%.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2007년도 추계학술대회 논문집
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• pp.205-205
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• 2007

The SiOC film of carbon centered system was prepared using bistrimethylsilylmethane and oxygen mixed precursor by the chemical vapor deposition. The chemical properties of the SiOC film were analyzed by the I-V measurement and FTIR spectra. The main bond of 950~1200 cm-1 was composed of the Si-C, Si-O-C and Si-O bonds. The leakage current of the SiOC film increased with the increasing of the carbon content, and the drift of the current was similar to the Si-O-C bond content.

• 한국재료학회지
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• 제27권1호
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• pp.12-18
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• 2017

Transparent organic-inorganic hybrid hard coating films were prepared by the addition of $SiO_2$ or $ZrO_2$, as an inorganic filler to improve the hardness property, filler was highly dispersed in the acrylic resin. To improve the compatibility in the acrylic resin, $SiO_2$ or $ZrO_2$ is surface-modified using various silanes with variation of the modification time and silane content. Depending on the content and kind of the modified inorganic oxide, transparent modified inorganic sols were formulated in acryl resin. Then, the sols were bar coated and cured on PET films to investigate the optical and mechanical properties. The optimized film, which has a modified $ZrO_2$ content of 4 wt% markedly improved in terms of the hardness, haze, and transparency as compared to neat acrylate resin and acrylate resin containing modified $SiO_2$ content of 8 wt%. Meanwhile, the low transparency and high haze of these films slowly appeared at $SiO_2$ content above 10 wt% and $ZrO_2$ content of 5 wt%, but the hardness values were maintained at 2H and 3H, respectively, in comparison with the HB of neat acrylate resin.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 1996년도 추계학술대회 논문집
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• pp.386-388
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• 1996

Low dielectric constant fluorinated oxide (SiOF) films were deposited using SiF$_4$/O$_2$/SiH$_4$mixtures by electron cyclotron resonance chemical vapor deposition (ECR CVD). Chemical composition of SiOF films was investigated by Fourier transform infrared spectroscopy (FT-lR). The fluorine content in the SiOF film observed by X-ray photoelectron spectroscopy (XPS). The dielectric constant decreased with increasing of the SiF$_4$ flow rate about 8sccm. The SiOF film, deposited with SiF$_4$=8 sccm, exhibited a F content of 5 atomic % and a relative dielectric constant 3.45. For evaluating SiOF films stability, humidity tests were performed.

• 한국재료학회지
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• 제15권11호
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• pp.730-734
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• 2005

Cr-Al-Si-N coatings were deposited on WC-Co substrates by a hybrid coating system of arc ion plating and DC magnet :on sputtering technique in $N_2/Ar$ mixture. The Cr-tll-Si-N coatings were synthesized with different Si contents. Their microstructure and mechanical properties were systematically investigated. The average size of crystallites largely decreases with the increase of Si content compared with Cr-Al-N. The microhardness of Cr-Al-Si-N coatings largely increases from 24 to 55 GPa. The enhanced hardness is believed to originate from the microstructural change by the fine composite microstructure of Cr-Al-N coatings with Si addition. The average friction coefficient of Cr-Al-Si-N coatings decreases from 0.84 to 0.45 with increasing Si content up to $16\;at.\%$.

• 한국주조공학회지
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• 제26권3호
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• pp.133-139
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• 2006

The effects of applied pressure, superheat and silicon content on the fluidity of Al-Si alloy during squeeze casting were investigated. The Fluidity of Al-7.0wt%Si alloy during squeeze casting was increased with applied pressure up to 60 MPa, meanwhile it rather decreased beyond that. Therefore, the optimum squeeze casting pressure was 60 MPa. The fluidity was increased with superheat up to $150^{\circ}C$. On the other hand, it rather decreased at the superheat of $200^{\circ}C$. The fluidity of Al-Si alloy during squeeze casting was decreased with silicon content in the range of $0.0{\sim}3.0\;wt%$, increased in the range of $3.0{\sim}13.0\;wt%$. The fluidity of Al-15.0 wt%Si alloy was lower than that of Al-13.0 wt%Si alloy.

• Elastomers and Composites
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• 제53권3호
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• pp.109-123
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• 2018

The effect of the silica content on the state and properties of silica-filled styrene-butadiene rubber/butadiene rubber (SBR/BR) compounds containing coupling and dispersion agents was evaluated by varying the content of silica from 50 to 120 phr. Bis-[(triethoxysilyl)propyl] tetrasulfide (TESPT) and zinc 2-ethylhexanoate (ZEH) were used as the coupling and dispersion agents, respectively. The maximum silica content in the pristine material was 80 phr, which increased to 120 phr upon the addition of TESPT and ZEH. The incorporation of TESPT considerably improved most of the rubber properties due to its coupling action and the suppression of silica flocculation, while further addition of ZEH resulted in additional improvements. The properties of the rubber compounds with different silica contents can be fully explained either by an enhancement of the rubber-silica interactions or by their deterioration due to an excessive amount of silica aggregates.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2004년도 Asia Display / IMID 04
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• pp.1099-1102
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• 2004

For the development of Pb-free low temperature sintering glass frits, $BaO-B_2O_3-SiO_2$ system was examined. The content of BaO and $B_2O_3$ was changed when the content of $SiO_2$ was fixed to 10 mol%. When the content of BaO was more than 60 mol% devitrification was observed. In the sintering temperature range between 520${\sim}$620 $^{\circ}C$, the optimum sintering temperature decreased as the content of BaO increased. When BaO ${\geq}$45 mol%, the glasses were crystallized after sintering. Candidate compositions are suggested in $BaO-B_2O_3-SiO_2$ system, which can replace the PbO containing glass system.

• Journal of Welding and Joining
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• 제8권2호
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• pp.27-39
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• 1990

The effect of silicon and manganese, in the ranges of 0.3% to 1.0wt% Si and 0.7 to 2.6wt%Mn, on the microstructure and mechanical properties of flux cored arc welded deposits have been investigated for the purpose of improving mechanical properties. Microstructure of weld metals was mainly influenced by manganese content, and manganese increased the volum fraction of acicular ferrite and refined the microstructure. Also, tensile properties were governed by manganese content, ultimate tensile strength and yield strength were increased by approximately 82MPa and 58MPa per 1% Mn addition to the deposit. Toughness was improved by increasing Mn content and lowering Si content. Optimal impact properties were obtained at above 1.8wt% Mn and below 0.5wt% Si. Acicular ferrite was predominant factor in improving mechanical properties. Formation of acicular ferrite was promoted by manganese and no direct relationship between AF(acicular ferrite) proportion and oxygen in weld metal was found.

• The Korean Journal of Ceramics
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• 제6권1호
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• pp.68-73
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• 2000

The effects of oxygen annealing on the carbon content in MgO thin films were investigated, MgO thin films were deposited on Si(100) substrate at different temperatures of 400 to $700^{\circ}C$ and different deposition rates of 3.4 to 11.6$\AA$/min. Using rf magnetron sputtering method. Carbon content change on the surface of MgO thin films with the oxygen annealing at different temperatures was investigated using various method. The carbon content decreased as the annealing temperature increased. $Pb(Zr_{0.53}Ti_{0.47})O_3$(PZT) thin films were deposited on the MgO/Si(100) substrates. The effects of carbon content on the phase formation and the electrical properties of PZT thin films were also investigated.