• Bulletin of the Korean Chemical Society
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• v.34 no.7
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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.

• Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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• 2004.11a
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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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• v.16 no.3
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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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• v.13 no.1
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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.

• Applied Chemistry for Engineering
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• v.27 no.5
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• pp.521-526
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• 2016

Some thiadiazole and dithiocarbamate derivatives were desinged and synthesized in order to study the potential use as anti- wear additives. Their anti-wear properties in three different base oils (DB-51, soybean, and 100 N) were evaluated using a four-ball wear tester (ASTM D4172). The solubilities of dithiocarbamate derivatives in the base oils were better than those of thiadiazole derivatives. The compounds containing oleoyl group rather than nonanoyl group gave good anti-wear properties. The solubilities and anti-wear properties were explained by the polarity of the compounds.

• Journal of the Korean Society for Heat Treatment
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• v.16 no.6
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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.

• Transactions of the Korean Society of Automotive Engineers
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• v.9 no.3
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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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• v.24 no.5
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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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• v.25 no.3
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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.

• Journal of the KSME
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• v.16 no.2
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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.