• Journal of the Korean Society for Heat Treatment
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• v.26 no.6
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• pp.306-316
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• 2013

Microstructure and fracture behavior of a multi-phase low-density steel were investigated. After hot-rolling and heat treatment, the microstructure of low-density steel was composed of coarse ferrite grains and elongated bands which include second phases such as austenite, martensite and ${\kappa}$-carbide depending on holding time during isothermal heat treatment. After tensile test, microcracks were observed at martensite or ${\kappa}$-carbide interface in the elongated bands. Coarse ferrite grains showed cleavage fracture behavior regardless of second phase. The cleavage fracture of ferrite could be attributed to their coarse grain size and solute atoms that increase ductile-to-brittle transition temperature of ferrite. Despite of the tendency of cleavage fracture in coarse ferrite grains, a specimen having coarse spheroidized ${\kappa}$-carbide particles in the elongated bands showed high total elongation of 30%. Thus, the easiness of plastic deformation in the elongated band seems to play an important role in retardation of cleavage crack formation in coarse ferrite grains.

• Journal of Powder Materials
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• v.12 no.2 s.49
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• pp.106-111
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• 2005

The effect of post-heat treatment on the coating characteristics and the fatigue strength of the gas flame thermally sprayed Stellite alloy coatings on $0.35\%$ carbon steel were investigated. The fatigue fracture surfaces of the heat treated samples were observed using SEM (Scanning Electron Microscopy). For as-sprayed samples, there was considerable scattering in the fatigue life due to the presence of the pores in the coating. After the post-heat treatment to improve the microstructural characteristics of the coating layer, the fatigue strength of the specimens was greatly improved, increasing with increasing the coating thickness. For the specimens with the 0.3mm and 0.5mm thick coating, the fatigue cracks originated in the substrate region just below the interface. On the contrary, for the specimens with the 1.0mm thick coating, they nucleated at the pore within the coating, and the fatigue strength was 2.6 times higher than that of the substrate due to the high fatigue resistance of the coating.

• Journal of Surface Science and Engineering
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• v.38 no.3
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• pp.118-125
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• 2005

Low temperature plasma treatment with different gases and rf powers were performed to improve the adhesion strength between polytetrafluoroethylene(PTFE) and electroless deposited copper. According to the research, $H_2$ plasma having hydrogen radical was more effective in surface polarity modification than $O_2$ plasma due to the defluorination reaction. However, surface roughness of PTFE was more increased with $O_2$ than $H_2$ plasma. PTFE treated with $120W-O_2$ plasma and $250w-H_2$ plasma, consecutively showed rougher surface than single step $250w-H_2$ plasma treated one and more hydrophilic than single step $120W-O_2$ plasma treated one. And it showed 5B tape test grade, which is better adhesion property than 1B or 3B obtained by single step plasma treatment. In addition, adhesion strength between PTFE and Cu deposit is also deeply affected by residual water on its interface.

• Journal of the Semiconductor & Display Technology
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• v.16 no.2
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• pp.66-69
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• 2017

In this paper, solution based Indium Zinc Oxide thin film transistors (IZO TFTs) were fabricated with PVP gate dielectric. To enhance the electrical properties, UV-O3 treatment is proposed on solution based IZO TFTs. The gate leakage current and interface trap density is compatible with conventional ZnO-based TFT with inorganic gate insulator. Especially, the UV-treated device shows improved electrical characteristics compared to the untreated device. These results can be explained by X-ray photoelectron spectroscopy (XPS) analysis, which shows that the oxygen vacancy of UV-O3 treatment is higher than that of no treatment.

• Proceedings of the Korean Fiber Society Conference
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• 2002.04a
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• pp.489-492
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• 2002

고분자/금속 복합재료는 현대 전자산업에 중요한 역할을 하고 있다. 그러나 이들간의 계면은 고분자의 수축 또는 계면 안정성의 저하로 인하여 박리가 일어나게 된다. 즉, 계면의 접합이 떨어지게 되면 전기 화학적인 반응이 계면에서 발생하여 드러난 금속부위는 산화되고 산소가 환원될 때 발생하는 OH기와 같은 라디칼들에 의해 금속과 고분자 사이의 결합이 파괴되어 금속표면으로부터의 고분자의 박리가 발생한다. (중략)

• 정보저장시스템학회:학술대회논문집
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• 2005.10a
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• pp.113-118
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• 2005

Small form factor optical disks for near-field optics using solid immersion lens were developed. Disk durability properties in terms of head-disk interface (HDI) properties were investigated by drag test, diamond like carbon film and lubricant film were coated on the small form factor disk to enhance HDI. Disks with glass substrates and lubricant films after heat treatment showed more durable characteristics. Coverlayers made of UV resin were uniformly coated by spin coating In which the ski-jump could not be formed by adopting outer ring technique.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1999.11a
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• pp.495-497
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• 1999

In order to determine what influences the interfacial breakdown in EPDM/XLPE laminates, We made the breakdown test ceil and this was pressure controllable breakdown test cell. We make the needle electrode (tip radius: about 10 micrometer) using electrochemical method. We studied the interfacial silicone oil was higher than that with silicone grease. As a function of heat treatment time in a vacuum, interfacial breakdown strength increased much in XLPE/EPDM laminates pasted with silicone grease but increased a little in that with silicone oil.

• 한국초전도학회:학술대회논문집
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• v.15
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• pp.58-58
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• 2005

• Proceedings of the Korean Vacuum Society Conference
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• 2013.08a
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• pp.320.1-320.1
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• 2013

We have investigated the effect of surface passivation for crystalline silicon solar cell using ozone-based atomic layer deposited (ALD) $Al_2O_3$. We examined passivation properties such as uniformity, carrier lifetime, thickness, negative fixed charge density at AlOx/Si interface, and reflectance. The influences of process temperature and heat treatment were investigated using microwave photoconductance decay (PCD). Ozone-based ALD $Al_2O_3$ film shows the best carrier lifetime at lower deposition temperature than $H_2O$-based ALD.

• Transactions of the Society of Information Storage Systems
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• v.2 no.1
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• pp.26-31
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• 2006

Small form factor optical disks for near-field optics using solid immersion lens were developed. Diamond like carbon film and lubricant film were coated on the small form factor optical disk to enhance the head-disk interface(HDI) characteristics. The disk durability properties in terms of HDI phenomena were investigated by drag test. Disks with glass substrates and the lubricant films experienced heat treatment showed more durable characteristics. Coverlayers made of UV resin were uniformly coated by spin coating in which the ski-jump could be removed by adopting outer ring technique