• 한국윤활학회:학술대회논문집
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• 한국윤활학회 2004년도 학술대회지
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• pp.37-40
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• 2004

The impact/sliding wear tests have been performed in high temperature high pressure water in order to evaluate the effect of spring shape on the wear behavior of a spring supported tube for nuclear fuel fretting study. The results indicate that the tube wear volume and the size of the wear scar are closely related to each spring shape. From the analysis of the wear scar, it is possible to extract the real worn area (Aw) from the size of the wear scar (At). In addition, we found that the wear volume has a linear relation with the real worm area rather than the size of wear scar and this was only determined by each spring shape in the high temperature and pressure water condition. From the above results, it is possible to evaluate the wear resistant spring using the correlation between the variation of the real worn area and the wear behavior at each spring.

• Tribology and Lubricants
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• 제24권6호
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• pp.302-307
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• 2008

The running-in behaviour of the metal carbon coating (WC/C) was evaluated with regard to its applicability as wear-resistant coating for key components in engines. Reciprocating wear tests under lubricated condition employing an oscillating friction wear tester were performed to investigate the tribological behaviors of the coatings in ambient environment. Confocal microscopy and scanning electron microscopy were used to observe worn surfaces and the wear scars on the steel balls. Elemental composition of the coating and worn surfaces were characterized using Auger electron spectroscopy. The friction behavior of WC/C coating was comparable to common carbon-based coatings. Thin tribofilm was formed on the worn surface of the steel ball due to material transfer and tribochemical reaction whereas there was no evidence of tribofilm generation on the coating surface. indicating the chemical innertness of WC/C coating.

• Tribology and Lubricants
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• 제12권2호
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• pp.32-40
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• 1996

The tribological role of copper alloy fine particles in an additive is not well known compared to solid lubricants such as $MoS_{2}$ and PTFE. In this experimental investigation, a series of friction and wear test was undertaken to gain a better understanding of an additive containing copper alloy fine particles and to identify the effectiveness of copper alloy particles in improving tribological performance of the lubricant. Friction and wear of specimens under lubricated contact condition were studied and the worn surfaces were characterized by AES (Auger Electron Spectroscopy), SEM (Scanning Electron Microscopy) and optical microscopy. It was revealed that a copper-contained layer was formed and this layer resulted in considerable reduction in both friction and wear due to its lubricity and anti-wear property. The analysis of worn surface revealed that copper of the fine alloy particles in the additive helps healing the worn surface by plating and filling wear pits.

• Journal of Welding and Joining
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• 제19권5호
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• pp.540-547
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• 2001

This study has evaluated the wear behavior of PTA (Plasma Transferred Arc) Inconel 625 and Stellite 6 overlays on Nimonic 80A substrate. Nimonic 80A alloy was also included for comparison. In order to evaluate the wear performance, three-body abrasive wear test and pin-on-disk dry sliding wear test were performed. Microstructural development during the solidification of deposits is also discussed. Wear test results show that the wear rate of Stellite 6 deposit is lower than that of Inconel 625 deposit and Nimonic 80A. The sliding wear resistance of overlay deposits follows a similar trend to the abrasive wear resistance, but for Nimonic 80A. The main wear mechanisms were abrasive wear for Inconel 625 deposit, adhesive wear and delamination for Stellite 6 deposit in pin-on-disk dry sliding wear test and ploughing in three-body abrasive wear test. Cross sectional examinations of the worn surface of pin specimens after pin-on-disk dry sliding wear test implies that the plastic deformation near worn surface has occurred during the wear testing.

• Journal of Advanced Marine Engineering and Technology
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• 제9권1호
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• pp.74-88
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• 1985

The wear becomes the most complicated cause of making various machineries short lives. In the studies by many scholors so far, the accurate and perfect methods to eliminate it completely are not found yet owing to many affected factors. On this view point of Depositional Wear, the wear test with seven different specimens from the part of frequent usage of which are carbon steel, nickel, copper, aluminum, zinc, lead and tin was attempted to make clear the relation between the wear of different metals and their melting point, crystal structure, sliding speed, load and lattice factors. The results of this study are summerized as follows; 1) Worn amount of each metal is maximum when each metal is same quality. 2) The easier becomes the the formation of solid solution in the course of friction proceeding, the more it results in worn amount of each metal. 3) The samer is each metal in crystal structure as well as lattice factor, the more it results in worn amount of each metal. These results might be of use in designing machineries, selecting materials and operating machineries.

• 복식
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• 제39권
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• pp.21-37
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• 1998

This study researchs forms of Egyptian religious dress for studying formation-process of religious dress and its ornament. The study goes abreast literature and the very spot's materials also divides god's dress, priest's. Ancient an egytian worshiped mainly animals, step by step animal's humanization. So gods were expressed animal's face and human's body. Egypt god's costume is 1st, to take off upper hament and wear loin cloth on trousers 2nd only to wear short sheath skirt. 3rd to wear shout sheath skirt and to skirt and to wear loin cloth on there 4th to cover whole body and to open hand like mummy. Egype goddess' costume is largely to wear long sheath skirt up to the ankle and we can see selkit goddess's figure that wearing kalasiris after new dynesty. Priest had been a bald head and worn loin cloth and surrounded leopard's skin on there, but after the period of empire, worn a wig and worn less stoically. Also god had hung the lion's tail at symbol of the dignity and priest had put on sandals for a ceremony.

• Tribology and Lubricants
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• 제11권4호
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• pp.45-52
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• 1995

The wear behavior of alumina short fiber reinforced tin-bronze matrix composites was studied at the room temperature and an elevated temperature. The effect of the composition of specimens and the variation of wear conditions on the wear properties was examined by a pin-on-disc type wear testing machine. The wear mechanism according to the compositon of specimens at various wear conditions was discussed by the observation of the microstructure and the analysis of the composition on the worn surfaces. A thicker oxide layer on worn surfaces led to a lower wear loss because of the lubricating effect of oxide layers between pin and disc. As the testing temperature was raised to 350$^{\circ}$C, the fiber reinforced composites exibited markedly increased wear resistance even at a higher applied load since the reinforcement of composites with alumina fibers was not affected to a large extent by raising temperature. The results obtained by AES and EDS analysis indicated that the oxide layer of the worn surfaces formed at 350$^{\circ}$C was proved as Fe-oxide. This was explained by the faster formation of Fe-oxide than Cu-oxide at 350$^{\circ}$C.

• KSTLE International Journal
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• 제6권1호
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• pp.1-7
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• 2005

Wear model for predicting the vehaviour of a depth is considered in this paper. It is deduced from the energy and volume based wear models such as the Archard equation and the workrate model. A new parameter of the equivalent depth ($D_e$= wear volume /worn area) is considered for the wear model of a depth prediction. A concenpt of a dissipated shear energy density is accommodated for in the suggested models. It is found that $D_e$ can distinguish the worn area shape. A cubic of $D_e$($D_e^3$) gives a better linear regression with the volume than that of the maximmum depth $D_{max}e$($D_{max}^3$) does. Both $D_{max}$ and $D_e$ are used for the presently suggested depth-based wear model. As a result, a wear depth profile can be simulated by a model using $D_{max}$. Wear resistance from the concern of an overall depth can be identified by the wear coefficient of the model using $D_e$.

• Tribology and Lubricants
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• 제26권2호
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• pp.105-110
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• 2010

In order to investigate the wear behavior of aluminum alloy depended on different hardness of the mating tool steel, sliding wear tests were conducted. It was found that the wear characteristics pattern of aluminum alloy for sliding speed was not affected by the hardness of the mating tool steel. However, the effects of the hardness of the mating tool steel exhibited only in relatively low sliding speed ranges. At these ranges, the wear rate of aluminum alloy decreased when increasing the hardness of the mating tool steel. This was attributed by the fact that $Al_2O_3$ particles released from the aluminum worn surface were crushed and embedded on the mating worn surface with high hardness level. At the high sliding speed ranges, wear of aluminum alloy was hardly occurred by the formation of thick $Al_2O_3$ film on the worn surface, regardless of the hardness of the mating tool steel.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2004년도 춘계학술대회
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• pp.84-89
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• 2004

When the tube contacted to support, anti-vibration bar of the steam generator in nuclear power plant, the contact area is worn out by their relative displacement and contact force. Connors and Au-Yang found the relation between tube worn displacement and volume, or normal work rate at given gap size. The present analysis is obtained the relation between tube worn displacement and normal work rate at various gap size modifying Au-Yang's result. The results are compared with Connors and Yettisir and Pettigrew's results. The comparison shows that Yettisir and Pettigrew result is fairly good agreement with Connors and present results with gap clearance, 0.015in.