• Journal of Powder Materials
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• v.13 no.6 s.59
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• pp.450-454
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• 2006

Wear of steel plate was measured during unlubricated sliding against TiC composites. These composites consist of round TiC grains and steel matrix. TiC grain itself exhibits low surface roughness and round shape, which does not bring its counterpart into severe damage from friction. In our work a classical experimental design was applied to find out a dominant factor in counterpart wear. The analysis of the data showed that only the applied load has a significant effect on the counterpart wear. Wear rate of counterpart increased non-linearly with applied load. Amount of wear was discrepant from expectation of being in proportion to the load by analogy with friction force. Our experimental result from treating matrix variously revealed bimodal wear behavior between the composites and counterpart where a mode seems to result from the special lubricant characteristic of TiC grains, and the other is caused by metal-to-metal contact. The two wear mechanisms were discussed.

• Journal of the Korean Ceramic Society
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• v.52 no.6
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• pp.429-434
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• 2015

This study investigates the macroscopic wear behaviors of C/C and C/C-SiC composites coated with hafnium carbide (HfC). To improve the wear resistance of C/C composites, low-pressure chemical vapor deposition (LPCVD) was used to obtain HfC coating. The CVD coatings were deposited at various deposition temperatures of 1300, 1400, and $1500^{\circ}C$. The effect of the substrate material (the C/C substrate, the C/C-CVR substrate, or the C/C-SiC substrate deposited by LSI) was also studied to improve the wear resistance. The experiment used the ball-on-disk method, with a tungsten carbide (WC) ball utilized as an indenter to evaluate the wear behavior. The HfC coatings were found to effectively improve the wear resistance of C/C and C/C-SiC composites, compared with the case of a non-coated C/C composite. The former showed lower friction coefficients and almost no wear loss during the wear test because of the presence of hard coatings. The wear scar width was relatively narrower for the C/C and C/C-SiC composites with hafnium coatings. Wear behavior was found to critically depend on the deposition temperature and the material. Thus, the HfC-coated C/C-SiC composites fabricated at deposition temperatures of $1500^{\circ}C$ showed the best wear resistance, a lower friction coefficient, and almost no loss during the wear test.

• Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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• 1998.04a
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• pp.139-145
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• 1998

This paper addresses the R-curve properties, wear resistance, and erosion resistance of the two silicon carbide ceramics with different microstructures, i.e. , fine grained SiC and in situ-toughened SiC(IST SIC). Fine grained SiC exhibits a relatively flat R-curve behavior whereas the IST SiC exhibits a increasing R-curve behavior. The increasing R-curve behavior in IST SiC is attributed to relatively weak grain boundaries. The rate of material removal during wear tests and erosion tests was higher for IST SiC than that for fine grained SiC. This is attributed to the weaker grain boundaries in IST SiC than that in fine grained SiC. It is implied that fracture toughness in short crack regime should be taken into consideration in the interpretation of the microscopical material removal process. We show that the higher the strength of grain boundaries is, the higher wear and erosion resistances are.

• Tribology and Lubricants
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• v.24 no.6
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• pp.386-392
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• 2008

Friction and wear behavior of hard coated and surface treated steel with candidate processing methods for low velocity high pressure application investigated. Wear tests were carried out under specific region considering the operation condition of construction equipments under lubricated and unlubricated condition. Different tribological behavior analyzed with comparing the wear rate of counter part, morphology and topography of worn surface and the worn volume of samples and counter parts.

• Journal of Power System Engineering
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• v.15 no.5
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• pp.77-82
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• 2011

SiC particulate reinforced Al matrix composites with different SiC volume fractions were fabricated by thermal spray process. And the dry sliding wear test were performed on these composites using the applied load of 10 N, rotational speed of 30 rpm, radius of rotation 15 mm. Wear tracks on the Al/SiC composites were investigated using scanning electron microscope(SEM) and energy dispersive spectroscopy (EDS). It was observed that wear behavior of Al/SiC composites and formation of MML was changed dramatically according to reinforcement volume fraction.

• Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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• 1990.11a
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• pp.63-68
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• 1990

Friction and wear behavior of a unidirectional high modulus carbon fiber reinforced epoxy composite exposed to high and low humidity was experimentally examined with various sliding speeds. The results show that the moisture at the sliding surface greatly influences friction and wear properties of the composite. It is also discoverd that the difference in friction and wear behavior between samples with different fiber orientations is mainly due to the anisotropic properties caused by the microstructure of oriented graphite crystals in the carbon fibers and the macrostructure of fiber orientation in the matrix.

• Tribology and Lubricants
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• v.6 no.2
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• pp.88-93
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• 1990

Friction and wear behavior of a unidirectional high modulus carbon fiber reinforced epoxy composite exposed to high and low humidity was experimentally examined with various sliding speeds. The results show that the moisture at the sliding surface greatly influences friction and wear properties of the composite. It is also discoverd that the difference in friction and wear behavior between samples with different fiber orientations is mainly due to the anisotropic properties caused by the microstructure of oriented graphite crystals in the carbon fibers and the macrostructure of fiber orientation in the matrix.

• Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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• 1998.10a
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• pp.25-29
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• 1998

Sliding wear test and surface characterization techniques such as micro-Raman spectroscopy were employed to determine the effect of whisker content and orientation on the friction and wear behavior of SiC whisker reinforced alumina. Composites containing unidirectionally oriented whiskers were fabricated by novel technique Addition of SiC whiskers up to 20 vol.% lowered the friction and improved wear resistance. The results of this study indicated that highly disordered graphite and size of the layer behind the whiskers were responsible for variation of wear rate and friction coefficient.

• Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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• 2004.11a
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• pp.37-40
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• 2004

The impact/sliding wear tests have been performed in high temperature high pressure water in order to evaluate the effect of spring shape on the wear behavior of a spring supported tube for nuclear fuel fretting study. The results indicate that the tube wear volume and the size of the wear scar are closely related to each spring shape. From the analysis of the wear scar, it is possible to extract the real worn area (Aw) from the size of the wear scar (At). In addition, we found that the wear volume has a linear relation with the real worm area rather than the size of wear scar and this was only determined by each spring shape in the high temperature and pressure water condition. From the above results, it is possible to evaluate the wear resistant spring using the correlation between the variation of the real worn area and the wear behavior at each spring.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.47 no.3
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• pp.267-272
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• 2011

The behavior of abrasive wear on counterpart roughness of glass fiber reinforcement polyurethane resin (GF/PUR) composites were investigated at ambient temperature by pin-on-disc friction test. The friction coefficient, cumulative wear volume and surface roughness of these materials against SiC abrasive paper were determined experimentally. The major failure mechanisms were lapping layers, ploughing, delamination, deformation of resin and cracking by scanning electric microscopy (SEM) photograph of the tested surface. As increasing the counterpart roughness the GF/PUR composites indicated higher friction coefficient. The surface roughness of the GF/PUR composites was increased as the sliding velocity was higher and the counterpart roughness was rougher in wear test.