• Bulletin of the Korean Chemical Society
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• 제34권7호
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• pp.2044-2050
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• 2013

A series of poly(glycerol-succinic acid) dithiocarbamate and 1,3,4-thiadiazole dendrimers, which have potential as anti-wear oil additives, were synthesized. Their anti-wear properties in three different oils (100N, DB-51, and soybean) were evaluated using a four-ball wear tester. The results indicated that thiocarbamate dendrimers have moderate anti-wear properties in DB-51 oil, and 1,3,4-thiadiazole dendrimers exhibited good anti-wear properties in 100N and DB-51 oils. However, dithiocarbamate and 1,3,4-thiadiazole dendrimers were not effective anti-wear additives in soybean oil.

• 한국윤활학회:학술대회논문집
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• 한국윤활학회 2004년도 학술대회지
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• pp.111-116
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• 2004

Li-complex and urea type greases (each 10 species) which were furnished by Chang-Am LS, analyzed anti-wear performance into fretting wear tester & four-bail wear tester. from the results of fretting wear test, the wear volume of Li-complex greases are $4.6\~8.9mg\;and\;8.3\~14.4mg$ with the test of urea greases. The anti-wear performance for 4-ball wear test of greases produced results around 0.5mm at the value of WSD. The grease life performance were evaluated by SKF-ROF Grease Tester and wheel bearing life tester. From the results of SKF-ROF tester, the life performance evaluated by whole working time produced results $50\~300hr$ with the Li-complex greases and 100-1000hr with the urea greases. That is to say, in spite of severe condition at the higher of $10^{\circ}C$ reaction temp, the life performance with Urea type greases are much superior to Li-complex type greases. Prior to wheel bearing life tester, the grease selected performance evaluation(=anti-wear test) are tested by wheel bearing tester. In this results, we can confirm results those are similar with SKF-ROF tester. In this study, we can draw two major conclusions, one is that Li-complex greases are superior to urea greases with anti-wear properties and the other is that urea greases are much superior to Li-complex greases with life performance.

• Tribology and Lubricants
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• 제16권3호
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• pp.173-181
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• 2000

Friction, wear and corrosion characteristics of various MoS$_2$ bonded film lubricants were investigated to apply them to automotive wheel joints. MoS$_2$ bonded film lubricants were formulated by combinations of several additives and binders, and they were coated onto the pre-treated surfaces of specimens. Friction and wear characteristics were evaluated with Falex pin & vee-block test and LFW-1 block-on-ring test. For the corrosion resistant characteristics of the films, salt solution spray corrosion tests were performed. Results showed that MoS$_2$ bonded films containing both inorganic and organic corrosion-resistant additives yielded a synergy effect on anti-corrosion resistance. Also, binders having the better water-proof and thermal stability showed the lower friction and higher corrosion resistance.

• Corrosion Science and Technology
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• 제13권1호
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• pp.15-19
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• 2014

Recently, anti-fouling paints which does not include the poison components such as tin(Sn), copper(Cu) have been increasingly developed in order to inhibit the environmental contamination of the sea water. Moreover, the wear ratios of these anti-fouling paints are very important problem to prolong their life time in economical point of view. In this study, five types of anti-fouling paints as self polishing type were investigated on the relationship between their polarization characteristics and wear ratios. It was verified that there was apparently a good relationship between the wear ratio and polarization characteristics, for example, the wear ratio increased with increasing the impedance ratio, and increased or decreased with the corrosion potential shifting in the negative or positive direction respectively. In addition, the wear ratio decreased with decreasing the corrosion current density. Consequently, it is suggested that we can qualitatively expect the wear ratio by only measuring the polarization characteristics. Therefore, before the examination of the wear ratio was actually carried out in the field, the evaluation of polarization property in the laboratory may give a available reference data for their developments.

• 공업화학
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• 제27권5호
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• pp.521-526
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• 2016

알킬그룹과 에스터, 싸이오에스터, 아미드 등의 결합을 가지는 다양한 싸이아다이아졸과 다이싸이오카바메이트 유도체를 분자설계하고 합성하였다. 이들의 내마모제로써 사용 가능성 연구를 위하여 DB-51, 대두유, 100 N에 대한 용해도와 내마모 특성을 분자 구조 및 극성 비교에 따라 고찰하였다. 윤활기유에 대한 용해도는 다이싸이오카바메이트 유도체가 싸이아다이아졸 유도체 보다 좋았다. 싸이아다이아졸 유도체가 다이싸이오카바메이트 유도체 보다는 내마모 특성이 더 우수하였으며, 특히 알킬 그룹이 올레일 그룹일 때 가장 뛰어난 성능을 보여주었다.

• 열처리공학회지
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• 제16권6호
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• pp.335-340
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• 2003

To improve properties of wear resistance and anti-corrosion of the trivalent chromium platings, oxinitrocarbunsing and steam oxidation were conducted. Armophous trivalent Cr platings could be transformed to chromium carbides of high hardness, that showed low friction and wear rate. Even though micro-cracks were within as platings, superior anti-corrosion property was obtained by these treatments due to healing of cracks at the interface between the trivalent chromium platings and substrate.

• 한국자동차공학회논문집
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• 제9권3호
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• pp.51-59
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• 2001

A diesel engine oil formulated in KRICT and a commercial diesel engine oil (API CG-4) were tested by car and their Kinematic Viscosity, TAN, TBN, metal content, additive depletion, anti-wear property and IR analysis were analyzed. From the research, both of the tested oils had almost the same properties f3r the change of TAN and TBN, but the change of Kinematic Viscosity of formulated oil was slightly higher than that of commercial oil. The iron content in the commercial oil increased rapidly from 7000 km while that of the formulated oil was still low. These results were confirmed by the anti-wear test with a 4-ball wear test machine for the each samples. Also, for the commercial oil, the depletion factor of the Zn-DTP which was added as an anti-wear property did not change any more after 7000 km. But, that of the formulated oil changed continuously to 8000 km, which means that the ability to prevent wear of the sliding pairs exists for the formulated oil. From the analysis results of oil properties obtained by field test, it was found that the commercial oil could be used only within 7000 km, but the formulated oil could be used more than 8000 km without severe wear of the sliding parts in the diesel engine.

• Tribology and Lubricants
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• 제24권5호
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• pp.264-268
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• 2008

A large number of additives have been used with the efforts of improving the performance of lubricants used along with the development of internal combustion engine. In this study, nano-sized graphite was used as liquid-lubricant additive. In order to disperse graphite into oil, we esterified the nano-carbon manufactured by our company with various types of alcohol. After measuring the anti-wear in accordance with the types of alcohol and added concentration, it has been found that its anti-wear/friction decrease has been improved in case of adding 0.1% of the sample composed with C12/14 mixed alcohol & hexadecanol.

• Tribology and Lubricants
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• 제25권3호
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• pp.192-196
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• 2009

This paper presents the hardness and wear characteristic of bronze metals, which are manufactured by a sintering process with a high pressuring technology. A bronze metal with a high hardness and anti-wear properties is usually used for a high pressure cylinder and a pin-bush bearing. The new bronze metal in which is manufactured for this experimental study shows very high hardness of 192${\sim}$220 Hv compared with that of a conventional bronze metal of 120${\sim}$140 Hv. The high hardness of new bronze metals is strongly related to the radical reduction of wear volumes and an improved surface roughness of operated worn surfaces. As explained by previous many research works, the improved hardness of nonferrous metals may increase a load-carrying capacity and anti-wear properties of tribological components.

• 기계저널
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• 제16권2호
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• pp.122-127
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• 1976

It was reported in the Journal of KSME Vol. 15, No. 3 and No. 4, 1975 that could be finished the best smooth surface by applying frictional work to the metal surface. Even if we can finish the best smooth surface of methal, it is not available when it has not anti-wear. Present study tried to investigate the anti-wear and the characteristics of frictional worked surface by using the sliding contact between plain bearing of brass and frictional worked jornal of mild steel. The results were compared with the case of ground journal.