• Steel and Composite Structures
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• v.11 no.2
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• pp.169-181
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• 2011

The behavior of connections between open sandwich slabs and double steel skin composite walls in steel plate-concrete(SC) structure is investigated by a series of experimental programs to identify the roles of components in the transfer of forces. Such connections are supposed to transfer shear by the action of friction on the interface between the steel surface and the concrete surface, as well as the shear resistance of the bottom steel plate attached to the wall. Experimental observation showed that shear transfer in slabs subjected to shear in short spans is explained by direct force transfer via diagonal struts and indirect force transfer via truss actions. Shear resistance at the interface is enhanced by the shear capacity of the shear plate as well as friction caused by the compressive force along the wall plate. Shear friction resistance along the wall plate was deduced from experimental observation. Finally, the appropriate design strength of the connection is proposed for a practical design purpose.

• Elastomers and Composites
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• v.53 no.4
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• pp.234-238
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• 2018

The influence of reinforcing UHMWPE powder on the tribological and mechanical properties of HDPE was investigated. The circularizing of UHMWPE powder was improved by high-speed rotation to enhance particle distribution and flowability. HDPE composites reinforced with UHMWPE powder in the range of 0-50 wt% were prepared by co-rotating twin screw extrusion. The abrasion resistance, plane friction coefficient, tensile strengths, and impact strengths of the composites were investigated as a function of the UHMWPE content. An increasing UHMWPE content decreased the plane friction coefficient and increased the abrasion resistance and impact strength. It is expected that HDPE composites reinforced with spherical UHMWPE powder particles can be used to improve the durability of products such as pipes in the future.

• Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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• 1999.06a
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• pp.92-100
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• 1999

Friction characteristics of automotive friction materials according to the types of phenolic resin were investigated by using a pad-on-disk type friction tester. Four different simplified friction materials bound with Bakelite$^{TM}$ and Xylok$^{TM}$ phenolic resin were studied in this work. Two different modes of drag test(constant initial temperature test and constant interval test) were employed to analyze the effects of the binders on friction characteristics. Friction materials containing modified Xylok$^{TM}$ resin showed good heat resistance and friction stability. The results also showed that aramid fiber played important roles in improving friction stability and weard wear

• Proceedings of the Korean Geotechical Society Conference
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• 2002.10a
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• pp.419-426
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• 2002

In this study, the steel strip reinforcement bolted with braced angles is displayed skin friction resistance as well as passive resistance through existing the steel strip reinforcement. To understand pullout behavior characteristics, friction effects between soil and reinforcement are evaluated with the width of reinforcement, magnitude of surcharge, and existence of passive resistance member through laboratory pullout test. To analyze interference effects for passive resistance member, various tests are carried on case that the number, the location, and the spacing of braced angles are different. Using this test result, pullout resistance factor is calculated to consider location of braced angles and degree of interference for spacing ratio.

• Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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• 2000.11a
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• pp.11-17
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• 2000

The electric contact resistance between ball and disk was measured to estimate the real area of contact under dry and lubrication conditions. The results from the measured constriction resistance using the hypothesis of a single circular contact was compared with those of Hertzian contact theory and hardness. The resistance correlated well with the asperity contact area and friction when the ball slides on the flat disk spreaded with lubricant film. Therefore, the constriction resistance method was useful to identify the lubrication regimes with respect to various loads and speeds. The results of this work will aid in better prediction of lubrication regimes with respect to the operating conditions.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2004.10a
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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.

• Journal of the Korean Ceramic Society
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• v.33 no.5
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• pp.479-484
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• 1996

The tribological properties of ceramics are very important in the application to engineering ceramic parts such as mechanical seal slurry valve disc and so on. In this study the effect of graphite addition on the mechanical and tribological properties of RBSC/graphite composites were investigated. The composites were prepared by adding graphite powder to the mixture of SiC powder metallic siliconcarbon black and alumina. Bending strength water absorption friction coefficient the amount of worn out material at a certain time and maximum surface roughness(Rmax) of the prepared composites were measured and crystalline phases were examined with XRD. The composite containing 5 vol% graphite powder showed improved bending strength due to high green density and decreased friction coefficient and wear resistance. The friction coefficient and the wear resistance of the composite were increased by adding graphite powder up to 10 vol% They decreased however as increasing the amount of graphite powder more that 10vol% There was no linear relationship between the tribological properties and bending strength of the composites.

• Proceedings of the KSME Conference
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• 2001.11a
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• pp.876-881
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• 2001

DLC(Diamond-like carbon) films possess high hardness, low friction coefficient, and good wear resistance. Due to these properties, DLC films have been used extensively in magnetic hard disk industry. The objective of the present study was to investigate the influence of environmental condition on the tribological behavior of DLC coated hard disk. It is found that the tribological characteristics of DLC films are strongly affected by relative humidity and temperature. Specifically, the friction coefficient increases with increase in temperature at relative humidity of 50%. However, at 20% and 85% RH the effect of temperature was not significant. Also, the degree of wear could be observed using an AFM.

• Journal of the Korean institute of surface engineering
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• v.44 no.6
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• pp.233-238
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• 2011

The friction and wear characteristics of CrN and TiN coatings on SKD61 which is mold material using for extrusion of AZ80 magnesium alloy were investigated. The coatings were deposited by the arc ion-plating method, and the thickness were about $3.59{\mu}m$ and $3.28{\mu}m$, respectively. Reciprocating friction wear tests were conducted by varying pin load and temperature of counter substrate at un-lubricated condition. The pin loads were 11, 15 and 19 kgf, and the substrate temperatures were room temperature and $120^{\circ}C$. CrN coating which has a lower friction coefficient and a smaller adhesive wear with AZ80 magnesium alloy showed better wear resistance than TiN coating.

• Corrosion Science and Technology
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• v.5 no.6
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• pp.196-200
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• 2006

For the evaluation of corrosion resistance of Al 6061-T6 alloy, Tafel method and immersion test was performed with Friction Stir Weld(FSW) and Gas Metal Arc Weld(GMAW). The Tafel and immersion test results indicated that GMA weld was severely attacked compared with those of friction stir weld. It may be mainly due to the galvanic corrosion mechanism act on the GMA weld.