• 제목/요약/키워드: Friction Resistance

검색결과 894건 처리시간 0.028초

Shear strength of connections between open and closed steel-concrete composite sandwich structures

  • Kim, Woo-Bum;Choi, Byong Jeong
    • Steel and Composite Structures
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    • 제11권2호
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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.

Tribological and Mechanical Properties of UHMWPE/HDPE Composites

  • Na, Woo Seok;Lee, Kwang Ho;Kong, Tae Woong;Baek, Jung Youn;Oh, Jeong Seok
    • Elastomers and Composites
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    • 제53권4호
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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.

자동차용 마찰재에 사5되는 폐놀수지의 종류에 따른 마찰특성의 영향에 관한 연구 (Effects of the Phenolic Resins in the Automotive Friction Materials on Friction Characteristics)

  • 김성진;홍영석;장호
    • 한국윤활학회:학술대회논문집
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    • 한국윤활학회 1999년도 제29회 춘계학술대회
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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

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버팀재 볼트 접합형 강재스트립 보강재의 인발거동특성 평가 (An Evaluation of Pullout Behavior Characteristics of the Steel Strip Reinforcement Bolted with Braced Angles)

  • 김홍택;방윤경;정중섭;박시삼;김현조
    • 한국지반공학회:학술대회논문집
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    • 한국지반공학회 2002년도 가을 학술발표회 논문집
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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.

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전기 저항을 이용한 실접촉 면적과 윤활 영역의 예측 (Estimation of Real Area of Contact and Lubrication Regimes using Electric Contact Resistance)

  • 이홍철;김대은
    • 한국윤활학회:학술대회논문집
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    • 한국윤활학회 2000년도 제32회 추계학술대회 정기총회
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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.

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인산망간 피막의 마찰 마모 특성에 관한 연구 , (A Study on Friction and Wear of Manganese Phosphate Thin Film)

  • 박영도;유상희
    • 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.

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반응소결 SiC-graphite 복합체의 마찰마모특성 (Tribological Properties of Raction-Bonded SiC-Graphite Composites)

  • 백용혁;신종윤;곽효섭;박용갑
    • 한국세라믹학회지
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    • 제33권5호
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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.

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하드디스크 DLC 필름의 마찰 마모특성에 대한 온도와 습도의 영향 (Effects of Temperature and Humidity on the Friction and Wear Properties of DLC Film on the Hard Disk)

  • 안준양;김대은
    • 대한기계학회:학술대회논문집
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    • 대한기계학회 2001년도 추계학술대회논문집A
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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.

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마그네슘 압출용 금형의 내마모성 향상을 위한 CrN, TiN 코팅 (CrN and TiN Coatings for the Wear Resistance of Extrusion Mold for Magnesium)

  • 이수영;김상호
    • 한국표면공학회지
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    • 제44권6호
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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 Behavior of Arc Weld and Friction Stir Weld in Al 6061-T6 Alloys

  • Yoon, Byoung-Hyun;Kim, Heung-Ju;Chang, Woong-Seong;Kweon, Young-Gak
    • Corrosion Science and Technology
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    • 제5권6호
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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.