• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.22 no.8
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• pp.736-741
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• 2012

Squeak noise is studied by using the pin-on-disk system with aluminum pin and steel disk. Noise induced by friction is measured with respect to the normal loads and sliding speeds. The negative slope of friction-velocity curve is seen when the squeak noise occurs. It is found that the normal load influences on the sound level of squeak noise. From the hammering test, the major frequency of the squeak noise is shown to correspond to one of system modes, which implies that squeak phenomenon arises from the unstable system modes. The result of FE analysis shows that the major squeak mode is the bending mode of the pin.

• 제어로봇시스템학회:학술대회논문집
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• 1996.10b
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• pp.1436-1440
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• 1996

The wear mechanism of material is an important mechanic property to select a material's life and a optimum work condition. Although there are many researches about a wear mechanism of material, the pin-on-disc type tribotester is widely known to us. It is difficult to add a variable and heavy load in the existing pin-on-disc type tribotester to estimate this wear mechanism. And due to a rotation of a disc, it is impossible to add a constant force. But we can solve this problem by using a hydraulic servo system. Therefore, in order to investigate a wear mechanism of materials, it is necessary to design a hydraulic pin-on-disc type tribotester and construct a controller against a variable disturbance.

• Tribology and Lubricants
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• v.24 no.5
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• pp.234-240
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• 2008

It is well known that surface texturing improves the tribological properties of mechanical components for enhancing hydro-dynamic effect or serving as a micro reservoir. There are not, however, enough researches to reveal the effects of surface texturing on the tribological properties under grease lubrication which is used in lubricating many mechanical elements. In the present study, therefore, the effects of surface texturing on the tribological properties are investigated under grease lubrication based on an experimental approach. The results show that surface texturing decreases friction coefficient. It is found that the friction coefficient can be decreased by controlling the diameter and density of micro-dimple. The diameter of dimple is more effective under high load and low speed than otherwise. And, the density of dimple is effective under low load and high speed.

• Composites Research
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• v.23 no.2
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• pp.10-16
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• 2010

$Al_2O_3$ fiber and SiC particle hybrid metal matrix composites (MMCs) were manufactured by squeeze casting method investigated for their tribological properties. The pin specimens had different ratios of fiber to particle content but their total weight fraction was constant at 20 wt. %. Tribological tests were performed with a pin-on-disk friction and wear tester. The investigation of the dry tribological characteristics of hybrid MMCs were carried out at room temperature and elevated temperature of$100^{\circ}C$ and$150^{\circ}C$. The morphologies of worn surfaces were examined by scanning electron microscope (SEM) to observe tribological characteristics and investigate wear behavior. The results revealed that the wear resistance improved with the content of SiCp increased of the planar random (PR) MMCs at room temperature. At the elevated temperature, it revealed that the wear resistance of normal (N) MMCs was superior to that of the PR-MMCs due to PR-fibers were easily pulled out holistically from the worn surface. Meanwhile, the coefficient of friction decreased with the temperature increasing.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.14 no.3
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• pp.124-130
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• 2015

The purpose of this study is to investigate friction characteristics according to micro-dimple patterns. The surface texturing of micro-dimple patterns was tested to examine the friction of pin-on-disk using flat-on-flat contact geometry. The patterns of both dimple circle and groove pattern were adopted to carry out the effect of those ones. In the low loads, such as 13.8N and 27.7N, the friction coefficients of groove pattern were lower than those of dimple circle pattern. In many other comparisons of normal loads, the groove pattern had lower friction forces, which showed the effect of surface texturing. The relationship between sliding time and friction forces showed that the increase of friction forces of groove pattern were relatively lower than those of dimple pattern. In conclusion, the dimple patterns of dimple-circle pattern and groove pattern strongly contributed to reducing the friction between contacting materials.