• 한국안전학회지
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• 제23권6호
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• pp.7-13
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• 2008

It is important to prevent roll failure in hot rolling process for reducing maintenance cost and production loss. The relationship between rolling pass schedule and the work roll wear profile will be presented. The roll wear pattern is related with roll catastrophic failure. The irregular and deep roll wear pattern should be removed by On-line Roll Grinder(ORG) for roll failure prevention. In this study, a computer roll wear prediction model under real process working condition is developed and evaluated with hot rolling pass schedule. The method of building wear calculation functions for center portion abrasion and marginal abrasion respectively was used to develop a work roll wear prediction mathematical model. The three type rolling schedule are evaluated by wear prediction model. The optimum roll grinding methods is suggested for schedule tree rolling technique.

• 한국재료학회지
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• 제13권12호
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• pp.839-845
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• 2003

The abrasion and impact wear resistance were investigated on the hardfacing weld dispersed with the recycled hard metal(HM). The HM was composed of the tungsten carbide(WC) reinforced metal matrix composite. The cored wire filled with the 25-35wt.% HM and 2-8wt.% of the alloying element, Fe-75Mn- 7C(FeMnC), was used for the gas metal arc(GMA) welding. By using the cored wire of the 25wt.% HM and FeMnC addition, the weld showed mostly constant wear loss for the abrasion as a function of the FeMnC content. This was due to the insufficient amount of the tungsten carbide formed during the GMA welding. The FeMnC addition to the 35wt.% HM did not improve the abrasion wear property since the amount of the tungsten carbide formed was decreased with respect to the FeMnC amount. The 6wt.% FeMnC addition to the 35wt.% HM exhibited the better impact wear resistance than the hardfacing weld by 40wt.% HM.

• 한국윤활학회:학술대회논문집
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• 한국윤활학회 1998년도 제27회 춘계학술대회
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• pp.271-276
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• 1998

To apply the wear resistant steel plate for heavy duty vehicle, the wear characterisms of various kinds of commercial steel plates were invesigated by dry sand/rubber wheel tester which was tested under scratch abrasion mode. The wear tested pnaterials were boron steels which were manufactured by thereto machanical control process (TMCP) in order to achieve higher hardness. As the result of the test, wear resistance of steel plate increases with the hardness and carbon content. The wear loss of wear resistance steel plate (Hv440) is a half times than tinat of SWS490A (Hv160) steel plate in dry sand-rubber wheel test and the result in field test is similar to this dry sand/rubber wheel test result. Therefore, dry sand/rubber wheel tester can be used to predict the scratch abrasion life of the parts for heavy duty vehicle.

• Elastomers and Composites
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• 제56권2호
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• pp.85-91
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• 2021

In this study, different types and shapes of various particles produced on the asphalt pavement road were analyzed. Road dust at a bus stop was collected and was separated as per their sizes by using a sieve shaker. Tire-road wear particles (TRWPs), asphalt pavement wear particles (APWPs), mineral particles, plant-related particles, glass beads, glass particles, road paint wear particles, plastic particles, and fibers were observed herein. The types and shapes of the particles varied depending on their sizes. TRWPs larger than 500 ㎛ were not observed. TRWPs with a size of 212-500 ㎛ were rarely present, but many TRWPs with a size smaller than 212 ㎛ were observed. APWPs were observed for whole-particle sizes of below 1,000 ㎛. A variety of particles on the road would lead to lower friction between the tires and the road, thereby increasing the braking distance of vehicles. Most of the particles include mineral particles, glass particles, and APWPs with rough surfaces. Therefore, the abrasion of the tire tread would accelerate owing to friction with the tough particles.

• Tribology and Lubricants
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• 제39권6호
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• pp.250-255
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• 2023

This study applies various surface patterns to minimize material loss in construction equipment that is subject to severe wear due to sand, such as the wear-resistant steel plates of dump trucks or the teeth of excavators. The relationship between surface morphology and wear behavior is investigated using PLA+ polymer to observe the effect of the surface pattern. Five types of samples - smooth, concave, convex, wavy concave, and wavy convex designs - are created using a 3D printer. A wear experiment is conducted for a duration of 3 h using 6.5 kg of abrasive particles. The mass loss of the samples after the experiment is measured to assess the extent of wear. Additionally, the surface morphology of the samples before and after the experiment is analyzed using SEM and confocal microscopy. The study results reveal that the smooth design exhibits the highest wear loss, whereas the concave and wavy concave designs show relatively lower wear loss. The convex and wavy convex designs exhibit varying contact areas with the abrasive particles depending on the surface pattern, resulting in different levels of wear. Furthermore, a comparison between the experimental results and DEM simulations confirms the observed wear trends. This study reveals the relationship between wear damage according to surface pattern shape and is expected to be of substantial help in the analysis of wear and tear on agricultural and heavy equipment.

• Elastomers and Composites
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• 제49권2호
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• pp.149-154
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• 2014

실리카와 카본블랙을 함유한 SBR 배합고무를 대상으로 마찰 및 마모거동을 조사하였다. 인열에너지 이론을 배경으로 설계된 칼날형 마모시험기를 이용하였으며 마찰일의 크기가 SBR 배합고무의 마모속도에 미치는 영향을 평가하였다. 마찰일이 증가할수록 마모속도가 증가하는 power law관계를 확인하였다. 칼날형 마모시험기를 통해 기존의 간헐적 마모손실무게 측정 대신 연속적 마모이동거리 측정이 가능했으며 보다 정확한 마모속도를 결정할 수 있었다.

• Journal of Welding and Joining
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• 제16권2호
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• pp.73-83
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• 1998

This study investigated the relationships between the microstructure and the wear resistance of hardfaced iron/chromium alloys to examine the low stress abrasive wear mechanism. The effects of volume fraction of reinforcing phases(chromium carbide and eutectic phase) were studied. The alloys were deposited once or twice on a mild steel plate using a self-shielding flux cored arc welding process. The low stress abrasion resistance of he alloys against dry sands was measured by the Dry Sand/Ruber Wheel Abrasion Tester (RWAT). The wear resistance of hypoeutectic alloys, below 0.36 volume fraction of chromium-carbide phase (VFC), behaved as Equal Pressure Mode (EPM) for the inverse rule of mixture whereas the wear resistance of hypereutectic alloys, above 0.36 VFC, represented Equal Wear Mode (EWM) for the linear rule of mixture.

• 대한치과보철학회지
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• 제41권6호
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• pp.747-761
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• 2003

Statement of problem. The proper materials of attachments for implant retained overdenture are unknown, such as the correlation between retention and abrasion, as well as the types of materials that are suitable for patrix and for matrix individually. Purpose of this study. The aim of this study was to select a proper clinical attachment system for a successful treatment as well as patient satisfaction. Methods. Retention and abrasion of 14 commercial attachments were measured during 15,000 removes. Results. A retentive part (matrix) which requires elasticity has to be made of gold while the patrix part which does not require elasticity has to be made of titanium. This gold matrix / titanium patrix combination showed the most retentive force and the least retention loss.

• Tribology and Lubricants
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• 제16권1호
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• pp.1-8
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• 2000

Friction and wear tests have been performed on nylon, acetal resin, and PTFE (polytetrafluoroethylene), in reciprocating dry sliding conditions against steel discs. According to the results, acetal resin showed the lowest wear rates and PTFE exhibited the lowest friction coefficient. The prominent wear mechanisms found were adhesion and abrasion.

• 한국안전학회지
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• 제18권3호
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• pp.14-21
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• 2003

This study deals with the influence of ceramic coating on characteristics of friction and abrasion of aluminum allot(7075 T6) used in mechanical casting. In this research, frictional wear characteristic of ceramic coating materials such as $A1_2O_3$, $Si_3N_4$, SiC was investigated using aluminum alloy(7075 T6) and stainless 403 cast iron under room temperature and normal air pressure. The coating layer was observed using SEM. The conclusions are as follows: 1) Friction coefficients of $A1_2O_3$, SiC and $Si_3N_4$ are obtained 0.63 0.56 and 0.54 respectively. 2) Abrasion resistance of stainless 403 cast iron with $Si_3N_4$ is the best among the ceramic coating materials. 3) Abrasion mechanism of aluminum alloy(7075 T6) coaled with ceramic material and stainless 403 cast iron is caused by brittle fracture. 4) Coating the ceramic material on the aluminum alloy(7075 T6) can effectively increase the antiwear, impact properties, and corrosion resistance.