• 대한기계학회:학술대회논문집
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• 대한기계학회 2003년도 추계학술대회
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• pp.1168-1173
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• 2003

When the tube contacted to support and antivibration bar of the steam generator in unclear power plant, the contact area is worn out by their relative displacement. In the study, wear depths of the tube inclined to tube support and antivibration bar are approximately predicted by a method using the contact load and relative displacement. In the case of the inclined contact, the results show wear depths of the steam generator tube predicted by the impact model are larger than those by the sliding model.

• Tribology and Lubricants
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• 제24권6호
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• pp.386-392
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• 2008

Friction and wear behavior of hard coated and surface treated steel with candidate processing methods for low velocity high pressure application investigated. Wear tests were carried out under specific region considering the operation condition of construction equipments under lubricated and unlubricated condition. Different tribological behavior analyzed with comparing the wear rate of counter part, morphology and topography of worn surface and the worn volume of samples and counter parts.

• 한국공작기계학회논문집
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• 제14권6호
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• pp.16-21
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• 2005

The cutting characteristics of hardened steel(AISI 52100) by PCBN tools is investigated with respect to cutting force, workpiece surface roughness and tool flank wear by the vision system. Hard Owning is carried out with various cutting conditions; spindle rotational speed, depth of cut and feed rate. Backpropagation neural networks(BPNs) are used for detection of tool wear. The input vectors of neural network comprise of spindle rotational speed, feed rates, vision flank wear, and thrust force signals. The output is the tool wear state which is either usable or failure. The detection of the abnormal states using BPNs achieves $96.8\%$ reliability even when the spindle rotational speed and feedrate are changed.

• 한국공작기계학회논문집
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• 제11권6호
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• pp.24-30
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• 2002

The friction/wear testing has been carried out for investigating the tribological characteristics between a conventional screw and tribotreated one. The tribotreated screw is manufactured by blasting a fine polymer power to the heat-treated surface of the conventional screw. The injection molding pressure that is developed between the screw and the cylinder has been applied to the rubbing surface on the specimen in a pin-on-disk wear tester. The measured results show that the friction coefficient and wear rate of a tribotreated screw are relatively low compared with the conventional one. This means that the tribotreated screw may be recommended for using an injection mold machine.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2003년도 춘계학술대회 논문집
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• pp.651-655
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• 2003

The rolling-stocks used in conventional line have suffered wheel problems due to lack of adaptability with track. These brought out severe wheel flange wear, these have caused unstable ride characteristics of rolling-stock. Especially, Wheel flange wear is severely influenced by wheel profile but lateral suspension characteristics. This study was started to induce wheel profile suitable for domestic railway environment. Thus, we analyzed the wear characteristics of wheel profiles that are being applied to railway rolling-stock in KNR. To analyze wheel wear characteristics, we have conducted experiment studies for passenger rolling-stock and obtained useful datum.

• 한국윤활학회:학술대회논문집
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• 한국윤활학회 2000년도 제32회 추계학술대회 정기총회
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• pp.298-303
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• 2000

The 3 mol% yttria stabilized zirconia (3-Y PSZ) powder was heat treated at 50 0$^{\circ}C$ to evaporate the polymer binder and stabilize the tetragonal phase. The wear experiments were carried out on a ring-on-plate type reciprocating wear tester at selected temperatures with in the range room temperature to 600$^{\circ}C$ The results show that the heat treatment of powder decreases the wear rate due to the reduction of microcracks and pores in coatings and the stabilization of the tetragonal phase. Powder heat treatment enhanced the quality of the coating layer by removing remnant gases during coating process and the powder heat treatment at which tetragonal phase is stable diminished phase ratio of monoclinic. These two effects improved wear resistance characters.

• 한국윤활학회:학술대회논문집
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• 한국윤활학회 1996년도 제24회 춘계학술대회
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• pp.45-54
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• 1996

The effect of graphite on the frictional characteristics of Cu-based sintered friction materials was studied by pin-on-disk type wear test. A study has been carried out concerning the optimum concentration of graphite in sintered friction material to obtain the minimum wear rate and low friction coefficient . Friction coefficient and wear rate were increased as increasing the content of graphite in the matrix. In the study the optimum concentration of graphite was 19vol % to get the minimum wear rate and optimal frick'ion coefficient.

• 한국윤활학회:학술대회논문집
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• 한국윤활학회 2002년도 proceedings of the second asia international conference on tribology
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• pp.227-228
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• 2002

One of the serious challenges in developing rotary compressor with HFC refrigerant is the prediction of scuffing times and wear amounts between vane and roller surface. In this study, the tribological characteristics of sliding surfaces using roller-vane geometry of rotary compressor were investigated. The sliding tests were carried out under various sliding speeds, normal loads and surface roughness. During the tests, friction force, wear scar width, time to failure, surface temperature, and surface roughness were monitored. Because severe wear was occurred on vane surface, TiN coating was applied on sliding surfaces to prolong the wear-life of vane-roller interfaces. From the sliding tests, it was found that there was the optimum initial surface roughness to break in and to prolong the wear life of sliding surfaces. Depending on load and speed, the protective layers, which were composed of metallic oxide and organic compound, were formed on sliding surfaces. Those would play an important role in the amount of friction and wear between roller and vane surfaces.

• 한국군사과학기술학회지
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• 제20권1호
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• pp.12-17
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• 2017

In this paper, causes of wear on high pressure seals for suspension are analyzed, and the result of reproduction test and verification on improved design are described. First, by performing the observation of worn surfaces and its failure analysis, the primary cause of wear on the seals are analyzed. The result of analysis shows that the main failure mechanism of wear is a fatigue wear, and test criteria for failure reproduction are set up with consideration for frequency condition, surface roughness and pressure. Durability comparison test on the condition of low amplitude and high frequency is carried out. And, it is found that the durability of wear on seals by increasing hardness of cylinder and managing for surface roughness is enhanced.

• 동력기계공학회지
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• 제13권6호
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• pp.123-128
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• 2009

The effects of temperature and initial crack length on the impact fracture behavior for the side plate material of FRP ship were investigated. And the effects of the counterpart roughness and sliding distance on the volumetric wear of same material were investigated as well. Impact fracture toughness of GF/PE composites displayed maximum value when the temperature of specimen is room temperature and $50^{\circ}C$, and with decreasing the temperature of specimen, impact fracture toughness decreased. Impact fracture energy of GF/EP composites decreased with increasing the initial crack length of specimen, and this value decreased rapidly when the temperature of specimen is lowest, $-25^{\circ}C$. It is believed that sensitivity of notch on impact fracture energy were increased with decreasing the temperature of specimen. With increasing the sliding distance, the transition sliding distance, which displayed different aspect on the friction coefficient and the volumetric wear loss, were found out. Counterpart roughness had a big influence on the wear rate at running in period, however the effect of counterpart roughness became smaller with sliding speed increase in. Volumetric wear loss were increased with increasing the applied load and the counterpart roughness.