• Tribology and Lubricants
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• v.8 no.2
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• pp.35-43
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• 1992

취성재료의 마멸천이기구를 규명하기 위해 반무한탄성체상에 표면균열이 존재할 때 그 위를 헤르쯔 접촉하중이 이동할 경우를 해석모델로 하여 선형파괴역할을 도입하여 해석하였다. 해석방법으로는 표면균열을 인상전위의 연속분포로 치환하여 Erdogan-Gupta의 방법으로 균열끝면의 응력확대계수를 구하여, 취성재료의 균열전파조건인 Erdogan-Sih Criterion을 사용하여 그 전파특성을 해석하였다. 본 논문에서는 마멸율이 적은 마멸에서 마멸율이 큰 마멸로 전이할 때 급격한 표면손상과 마찰계수의 급격한 증가를 동반하므로 이에 대한 해석에 중점을 두었다. 해석결과는 접촉하중과 마찰계수의 증가는 표면균열의 전파를 야기시켜 대규모 마멸입자를 생성시키게 됨을 보여주었다.

• Transactions of the Korean Society of Mechanical Engineers
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• v.19 no.9
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• pp.2122-2132
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• 1995

There are some cases which require to grasp the abrasion resistance property in the fields of the high-technology to be required the high specific strength and modulus. In this study, wear test with the various test temperature and velocity were performed in the SiCw/A16061 composite and A16061 matrix using the wear test machine of the ring-on-disc type. As the results, the friction and wear properties by various test temperature and velocity were examined. The worn surface has observed by scanning electron microscope in order to examine the wear mechanism.

• Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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• 2002.05a
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• pp.73-79
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• 2002

Fretting wear test in room temperature air was performed to evaluate the wear mechanism of fuel rod using a fretting wear tester, which has been developed for experimental study. The main focus was to compare the wear behaviors of fuel rod against support springs at different contact geometries (i.e. concave and convex) and slip directions (axial and transverse). The wear on the tube was examined by the surface roughness tester, which measures the volume. The result indicated that with change of contact geometry from 5N of normal load to 0.1mm gap, wear volume of tube Increased in the condition of concave spring, but slowly decreased in convex spring. From the results of SEM observation, wear mechanism of each test condition was also depend on the above contact parameters. The wear mechanism of each test condition in room temperature air is discussed.

• Transactions of the Korean Society of Mechanical Engineers
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• v.17 no.12
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• pp.3083-3093
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• 1993

Friction and wear at ceramic coated surfaces of aluminum alloy were experimentally studied using a Ring-on-Block wear test machine. Ceramic materials coated on aluminum alloy surfaces were WC, CrC, $Al_{2}O_{3}$ by a plasma spray; and $Al_{2}O_{3}$,$Al_{2}SiO_{5}$, $Na_{2}B_{4}O_{7}$,$Na_{4}P_{2}O_{7}$, and $Al_{2}O_{3}-ZrO_{2}$ composite coating by an Anodic Spark Depositon. They were tested under the sliding wet contact and compared with aluminum alloys and steels. Test results showed that ceramic coated surfaces, in general, have better anti-wear property than those of aluminum alloys due to increase in the surface hardness ; however, they also showed higher coefficients of friction and changes in wear mechanisms, resulting in brittle fractures.

• Journal of the korean Society of Automotive Engineers
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• v.3 no.1
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• pp.1-4
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• 1981

Clutch disc 의 facing은 사용할 때마다 마찰로 인하여 마멸된다. 마멸함에 따라 clutch cover의 구조상 clutch cover의 release lever가 올라와 clutch release bearing (thrust bearing)과의 간 극이 작아져서 드디어 이 간극이 없어지게 되면 release lever가 clutch release bearing을 누르게 되어 평상에도 clutch가 절반 정도로 떨어지는 상태로까지 됨으로써 clutch의 완전한 연결을 할 수 없어 slip이 일어나게 된다. 이상과 같은 문제점들을 해소하기 위하여 clutch의 control system을 수시로 조정하지 않으면 안되며 이러한 번거로움을 피하기 위하여 release lever가 올라옴으로써 release bearing과의 간극이 작아져서 자동적으로 일정한 간극을 유지하여 clutch의 slip을 방지하고 clutch기구의 내구성을 향상시키기 위한 것이 무조정식 release cylinder, 혹은 clutch adjuster이다. 이에 대한 신형식 두 종류의 구조, 작동 및 특징에 대하여 해설하여 본다.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2004.05a
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• pp.60-60
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• 2004

광디스크 미디어 저장기기에 있어서 음악과 영상을 재생하는 광디스크 플레이어의 기구부품 중 턴테이블은 디스크를 장착, 고정하여 디스크에 기록된 신호를 재생케 하는 광디스크 메커니즘의 중요기능 부품이다. 특히 별도의 클램퍼 없이 턴테이블에 부설된 탄지력만으로 디스크를 장착, 고정하는 슬림형 플레이어에서 스핀들 모터의 회전 시 턴테이블에 장학된 광디스크의 슬립은 재생에러를 야기한다. 스피닝 회전속도가 증가할수록 디스크의 슬립을 방지하기 위해서는 디스크와 턴테이블의 증가된 마찰력이 요구된다.(중략)

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2001.10a
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• pp.159-163
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• 2001

마찰구동은 다른 구동방식에 비하여 구조가 간단하고, 기계적인 정도를 얻기 쉬우며, 백래쉬 등에 기인하는 비선형 요소인 로스트모션이 없고 관성이 작아 구동력이 작은 이점이 있다. 그 반면에 접촉부에서 미끄럼이 발생하여 큰 구동력을 얻기 어렵고 마찰저항에 의하여 마멸이 생기는 결점이 지적되고 있다. 본 연구에서는 초정밀가공기용 위치결정기구로 마찰구동기구를 사용하기 위하여 위치 결정도에 관한 설계, 구동력의 설계 및 재료의 선택에 관하 여 분석하고 시작품을 제작하여 특성을 연구하였다.

• Transactions of the Korean Society of Mechanical Engineers
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• v.17 no.6
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• pp.1404-1411
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• 1993

This study was undertaken to investigate the corrosive wear charateristics upon various transformation condition of austempered low-alloy ductile cast iron in corrosive environments against mating specimen made of the hardened SM45C. The corrosive wear test was carried out by rubbing the annular surface of two test pieces in distilled water and aqueous solution at constant sliding speed of 0.5m/s. In severe wear region, the corrosive wear rate Wc increased hastily with NaCl concentration owing to intermetallic adhesion but Wc went down slowly in mild wear region due to lubricating effect of the corrosion product. The critical sliding distance decreased with increasing NaCl concentration due to increased generation rate of the corrosion product and the specific corrosive wear rate has maximum in 1% NaCl aqueous solution at mild wear region. With the variation of matrix, the corrosive wear resistance of the fine acicular bainite was higher than that of coarse upper bainite because of reducing the local cell reaction by carbides. A growth in volume fraction of retained austenite in matrix increased the Wc due to soften surface, but has a declining tendency of Wc in mild wear region.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.24 no.2 s.173
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• pp.464-471
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• 2000

The fracture and wear behavior of dental composite resins containing prepolymerized particle fillers were investigated. Composite resins such as Metafil, Silux Plus, Heliomolar and Palfique Estelite were selected as specimens and contents of filler in specimens in order to evaluate the effect of prepolymerized particle fillers in fracture and wear characteristics. Ball on flat wear tester was used for the wear test at room temperature. The friction coefficient of Metafil was quite high relatively, and the wear resistances of Silux Plus and Palfique Estelite were better than those of Metafil and Heliomolar at the same experimental condition. It was found that the main wear mechanism was abrasive wear containing of plastic deformation of dental material.

• Transactions of the Korean Society of Mechanical Engineers
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• v.14 no.2
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• pp.399-406
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• 1990

This paper is studied to know corrosive wear mechanism of STS304 steel on atmospherical temperature against mating material as the same. The corrosive test was carried out by rubbing the annular surface of two test pieces in distilled water and NaCl aqueous solution. The corrosive wear mechanism was investigated by S.E.M. The experimental results show that there is one Lcr transferring from severe wear to mild wear on change of NaCl concentration and atmospherical temperature, and which is the other still remaining in server wear state. It was found that the critical sliding distance Lcr shorten with increasing NaCl concentration but it is longer with ascending atmospherical temperature and the mild wear state still continues under the condition of high generation rate and elimination rate of the corrosive product. Considering upon the result, the model of corrosive wear mechanism is proposed.