• The Korean Journal of Rheology
• /
• v.7 no.1
• /
• pp.50-59
• /
• 1995

겨울용 타이어인 '발포고무 타이어'의 트레드에 적용되는 발포고무의 물성과 마찰 및 마모특성을 조사하였다. 천연고무인 SMR-CV60과 합성고무인 BR-01(Cis-1, 4 Polybutadiene)을 70:30 비율로 혼합하였고 발포제로는 개질화된 azodicarbonamide (상품 명:UNICELL AD#2)을 변량 첨가하여 다양한 발포도의 발포고무를 준비하였다. 발포도의 증 가로 발포고무의 Young's modulus와 파괴에너지는 점진적으로 감소하였으나 Tan $\delta$ 는 일정한 값을 유지하였다. 매끄러운 유리표면위에서 높은 마찰계수를 보인 발포고무는 발포 도의 증가로 크게 감소하였고 거친 표면일수록 마찰계수는 상승하였다. 이같은 마찰계수의 증감경향이 교차되는 발포도는 30~40%이었다. $0^{\circ}C$에서의 마찰계수도 유리 표면에서감소하 고 거친표면에서 상승하는 경향을 보였으며 증감경향이 교차하는 발포도는 20%로 낮아졌 다. 마찰표면을 마그네시아 분말로 처리하면 전반적으로 마찰계수는 감소하였고 발포도의 크기에 관계없이 마찰표면이 거칠수록 큰 마찰계수를 나타내었다. 발포고무의 발포도가 커 지면 마모손실량도 비례하여 증가하였으며 발포도가 낮은 고무에서는 비교적 규칙적인 융기 간격이 보였으나 발포도가 30%이상으로 되면 불규칙적인 마모표면과 더불어 많은 마모 부 스러기가 관찰되었다.

• Elastomers and Composites
• /
• v.36 no.2
• /
• pp.121-129
• /
• 2001

The friction characteristics of natural rubber plates under various conditions including sliding speed, normal force, hardness, lubrication conditions and thickness of plate are analyzed experimentally. The frictional force and normal force are measured by a tester pin and a load ceil with strain gages. Experimental results suggest that the coefficient of friction decreases with increasing the hardness of rubber and decreasing the thickness of plate. The effect of sliding speed is not significant over the speed range employed. The coefficient of friction is found to be about 0.1 under oil lubrication condition and varies from 0.9 to 3.9 under no lubrication condition.

• International Journal of Highway Engineering
• /
• v.12 no.3
• /
• pp.131-137
• /
• 2010

In this paper, overseas criteria and research results were reviewed to develop a rational criterion proper to domestic airport runways on measurement of friction coefficient and removal of rubber deposit. The friction coefficients of the runways of the Incheon International Airport were measured by the ASFT(Airport Surface Friction Tester) from August 2007 to July 2009 and the data at intensively landed points were analyzed. Variation of the friction coefficient due to accumulation and removal of tire rubber was analyzed and seasonal influence on the variation were investigated by pavement types. The friction coefficient steadily decreased over a long term despite periodical removal of the rubber deposits. The variation of the friction coefficient in summer was larger than other seasons and asphalt pavement was more sensitive to the seasonal influence than concrete pavement. The friction coefficient of the asphalt pavement with macro texture was even larger than that of early age concrete pavement with micro texture. The variation of the friction coefficient of the asphalt pavement due to the deposit and removal of the tire rubber was also larger than that of the concrete pavement.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.11 no.4
• /
• pp.1197-1202
• /
• 2010

We have studied on the frictional characteristics for mounting rubbers varieties structures on the automotive engine. This paper are using a test apparatus developed in the laboratory, friction and wear characteristics of various rubbers have been analyzed by experimental study. Frictional characteristics has been measured from the normal force and friction force under various operating conditions, such as, loads, speed and temperatures. Therefore, the rubbers are used in a several varieties structures as well as automotive, the relations between the various conditions and frictional characteristics have been investigated.

• Journal of Korean Society of Steel Construction
• /
• v.28 no.4
• /
• pp.223-229
• /
• 2016

This study proposes a new technology for a smart damper with flag-shaped behavior using the combination of magnetic friction and rubber springs. The magnet provides friction and, thus, energy dissipation, and the rubber springs with precompression contribute to present self-centering capacity of the damper. To verify their performance, this study conducts dynamic tests of magnet frictional dampers and precompressed rubber springs. For the purpose, hexahedron Neodymium (NdFeB) magnets and polyurethane rubber cylinders are used. In the dynamic tests, loading frequency varies from 0.1 to 2.0 Hz. The magnets provide almost perfect rectangular behavior in force-deformation curve. The rubber springs are tested without or with precompression. The rubber springs show larger rigid force with increasing precompression. Lastly, this study discusses combination of rigid-elastic behavior and friction to generate 'flag-shaped' behavior for a smart damper and suggests how to combine the magnets and the rubber springs to obtain the flag-shaped behavior.

• Transactions of the Korean Society of Mechanical Engineers A
• /
• v.37 no.7
• /
• pp.905-912
• /
• 2013

Rubber is one of the most commonly used materials in various fields because of its unique viscoelastic properties. Friction occurs when a tire constantly makes contact with the ground. As a result, friction causes wear. The frictional energy caused by friction is a primary factor in the wear mechanism. The frictional energy is affected by various conditions (temperature, roughness of ground, shape of rubber, load, and materials). In this study, the analysis was preceded by considering the vertical load and the horizontal velocity to the rubber using ABAQUS/explicit. The contact pressure, and friction energy are derived using the shear force and slip distance. The actual behavior of the rubber test data were compared with the analysis results.

• Rubber Technology
• /
• v.24 no.2
• /
• pp.76-88
• /
• 2023

• Polymer(Korea)
• /
• v.37 no.3
• /
• pp.255-261
• /
• 2013

This paper introduced a new preparation method of a composite rubber by mixing BR (butadiene rubber) and CIIR (chloro-isobutyl rubber) for the purpose of improving frictional property of BR. Since BR has high abrasion and low frictional properties, its frictional property needs to be enhanced in order to be used as an outsole of a sport shoe. Such enhancement was difficult to achieve by simple blending of CIIR. In here, CIIR was added into BR matrix after CIIR was pre-crosslinked for a time period, and both high frictional and high abrasion resistance properties were achieved. Our experiments showed that the composite rubber blend of 60% of BR and 40% of pre-crosslinked CIIR had desired BR's frictional and abrasion resistance properties for sport shoes.

• Elastomers and Composites
• /
• v.31 no.4
• /
• pp.298-307
• /
• 1996

• Elastomers and Composites
• /
• v.36 no.1
• /
• pp.3-13
• /
• 2001

To resolve environmental problem of waste tire and asbestos and also to capitalize the wastes, we developed a new kind of friction material using scrap tire, potassium hexatitanate, filler, and friction modifier in which rubber made a continuous phase. The material containing 5, 20, 10, 20phr of potassium hexatitanate, phenol, friction modifier, $BaSO_4$, respectively showed good friction properties, high and stable coefficient or friction, and low wear rate.