• 한국윤활학회:학술대회논문집
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• 한국윤활학회 2002년도 proceedings of the second asia international conference on tribology
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• pp.155-156
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• 2002

During the sliding between a-CNx and $Si_3N_4$, applying nitrogen as environmental gas provided very low friction as the level of 0.01 in friction coefficient. In order to know the effect of the running-in process on the reduction of the friction, the effect of surface roughness of mating surface on friction was investigated. It was shown that smooth surface in wear scar of ball provided low friction coefficient. Friction coefficient after running-in was proportional to the Ry value of wear scar of ball. Also smooth thin transferred layer was observed on the wear scar of balls with an AFM after sliding test. Those results showed the smoothing of wear scar of ball, the generating of the transferred layer from CNx was necessary for low friction.

• Journal of Advanced Marine Engineering and Technology
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• 제23권4호
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• pp.440-446
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• 1999

This study is mainly concerned with the friction and wear properties for the specimens of crank shaft which are made of ductile cast iron. The friction and wear tests were carried out for the nor-malized ductile cast iron specimens and their properties were compared with each other at reheat-ing temperatures(550^{\circC,\; 600^{\circ}C,\; 650^{\circ}$) and in dry condition at different friction velocity(0.94 m/s 1.88m/s 2.83m/s) range. After austenized at $910^{\circ}C$ it is observed that the higher the reheating temperature is the hardness becomes decrease which is supposedly attributed to the fact that the amount of pearlite austenite matrix is rduced by reheating after normalizing and that as the reheating temperature goes up the pearlite generated is less and the interval between the pearlites were widened at last to make pearlite globular. At the low velocity the friction coefficient increase in the beginning and gets stabilized as the sliding distance increases. As the friction velocity grows the friction coefficient decreases suppos-edly since the abrasive wear is heavier at low velocity than at the high velocity as the friction tem-perature at low velocity is lower than at high velocity.

• 한국표면공학회지
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• 제43권6호
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• pp.278-282
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• 2010

In this research, the friction and wear characteristic behaviors of coating materials of TiAlN and CrAlN were investigated. The wear test was conducted in air and un-lubricated state using the reciprocating friction wear tester. Temperature were 50 and $120^{\circ}C$, and load were 3, 7, and 11 kgf for tests. By comparing the coefficient of friction and observing the wear microstructure, the friction and wear characteristic behaviors of TiAlN and CrAlN coating layers on SKD61 were investigated. The coefficient of friction of CrAlN coating was lower than that of TiAlN at all conditions. Therefore, CrAlN was suggested to be more advantageous coating than TiAlN for the extrusion mold of aluminum.

• Tribology and Lubricants
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• 제35권3호
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• pp.183-189
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• 2019

The driver seat of an automobile is in direct contact with the driver and provides the driver with a safe and comfortable ride. The seat consists of a frame, a rail, and many recliners. In recent years, strength and operating force measurement testing of the recliner have become vital for designing car seats. However, performance evaluation requires expensive testing equipment, numerous seat products, and considerable time. Therefore, the trend is to reduce experimentation through interpretation. This study examines the lubrication of solid lubricant for automotive seat recliners and confirms the friction and wear performance. In this study, the lubrication behavior of solid lubricants for car seat recliners is investigated to ascertain the friction and wear performance and to provide accurate values for the strength analysis. The friction material consists of a pin and a plate made from steel, which is widely used in recliners. The friction and wear under lubrication conditions are measured by a reciprocating friction wear tester. The friction coefficient is obtained according to the load and speed. Based on the obtained results, it is possible to achieve a reduction in the error of the test value and the analysis by providing the friction coefficient and wear of the lubricant. The results can be applied to the analysis of automobile seat design.

• 한국정밀공학회지
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• 제21권12호
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• pp.167-173
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• 2004

Recently, it has been reported that frictional behavior at nanometer scale can be different from that at macro scale. In this article, friction and wear tests were conducted using an AFM to investigate the effect of real contact area on the coefficient of friction and wear property. SiO$_2$, Hica, and SiGe were used in friction test and the AFM tip was Si$_3$N$_4$. The real contact area between an AFM tip and flat surface was calculated by the Johnson-Kendall-Roberts (JKR) theory. Wear specimen was Mica, and the diamond tip was used. We found that the coefficient of friction is constant below a critical area, but it is degraded over the area. Moreover, it is found that wear depth increased rapidly from a certain load and was degraded as a function of the number of the scanning cycles. Also, the range of scanning velocity used in this study had little effect on the wear depth.

• KSTLE International Journal
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• 제3권1호
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• pp.43-48
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• 2002

Dry sliding wear and friction test of CrN coaling on two types of aluminum alloy substrates,6061 Al and 7075 Al deposited by arc ion plating, was peformed with a ball-on-disk tribometer. The effects of normal Bead and the mechanical properties of substrate on the friction coefficient and wear-resistance of CrN coating were investigated. The worn surfaces were observed by SEM. The results show that surface micro-hardness of CrN- coated 7075 Al is higher than that of CrN-coated 6061 Al. With an increase in normal lead, wear volume increases, while the friction coefficient decreases. The friction coefficient of CrN-coated 6061 Al is higher than that of CrN-coated 7075 Al, while the wear-resistance of CrN-coated 6061 Al is lower than the CrN-coated 7075 Al's, which indicates that the substrate mechanical properties have strong inf1uences on the friction coefficient and wear of CrN coating. The main wear mechanism was fragments of CrN coating, which were caused by apparent plastic deformation of substrate during wear test.

• Tribology and Lubricants
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• 제5권1호
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• pp.12-20
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• 1989

The friction and wear behavior of molybdenum disulfide filled polymer composites sliding against metal has been investigated using pin-on-disc machine and microscope. The observed wear rates were reduced by the addition of MoS$_2$ to nylon and this can be attributed to the homogenous transfer of MoS$_2$ to the counteddace thereby modifying sliding conditions. The friction of filled and unfilled nylon was increased with increasing sliding speed, and the catastropic wear rate was occurred at high normal load. This have been explained by thermal degradation. In the case of HDPE, however, the wear rate was not always reduced by the addition of MoS$_2$ and the influence of MoS$_2$ was mainly even the opposite. Filled and unfilled HDPE had lower values of friction and wear rate than those of nylon. Micrographs appeared that the delamination of the worn surface in nylon/MoS$_2$ composite occurred and revealed that the worn surface of HDPE presented a number of characteristic features as wear grooves, pulls, and smears and crescents.

• 한국윤활학회:학술대회논문집
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• 한국윤활학회 1999년도 제29회 춘계학술대회
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• pp.203-208
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• 1999

Friction and wear test have been performed on nylon, polyacetal, and PTFE(polytetrafluoroethylene), in reciprocating dry sliding conditions against a steel disc. According to the results, polyacetal show lowest wear rates and PTFE was found to exhibit lowest friction coefficient. The prominent wear mechanism found were adhesion and abrasion.

• 한국공작기계학회논문집
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• 제14권2호
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• pp.1-7
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• 2005

In order to determine the wear Properties of PECVD ceramic coatings, wear process was evaluated using the coated pin of Falex Tribosystem. Coating materials deposited wear the TiC, TiN and Ti(CN). An experimental process was established to determine the tribological characteristics of friction and wear behavior under the variation of applied load, temperature and sliding distance by the Falex test machine. The experimental results indicate that TiN coating compared with TiC coating on e materials have e excellent friction and wear characteristics. However TiC coating compared i친 TiN coatings have a low friction coefficient with steel and good thermal stability, and Ti(CN) has the excellent anti-wear properly as well as the superiority of extreme pressure property. Compound coating compared wi simple coatings show improved tribological characteristics.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2004년도 추계학술대회 논문집
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• pp.1384-1389
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• 2004

In these days, wear resistance is an essential condition because the relative movement between machine parts is being accelerated and those connected with the drive parts transmit power and force. Also wear resistance is closely related to reliability and life of products, therefore the study on friction and wear is very important in many fields. In this paper, wear test was conducted to know properties about friction and wear of manganese phosphate being used widely. Test type is 1 ball on disk and we compared manganese phosphate thin film with non-coated material. Through this study, we could know the effect of this surface treatment method, and then it is assumed that the reliability of parts will be secure.