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REFERENCE LINKING PLATFORM OF KOREA S&T JOURNALS
> Journal Vol & Issue
Journal of the Korean Society of Tribologists and Lubrication Engineers
Journal Basic Information
Journal DOI :
The Korean Society of Tribologists and Lubrication Engineers
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Volume & Issues
Volume 26, Issue 6 - Dec 2010
Volume 26, Issue 5 - Oct 2010
Volume 26, Issue 4 - Aug 2010
Volume 26, Issue 3 - Jun 2010
Volume 26, Issue 2 - Apr 2010
Volume 26, Issue 1 - Feb 2010
Selecting the target year
A study of Frictional Behavior of SCM415 Steel as a Function of Density of Micro Dimples
Cho, Min-Haeng ; Lee, Seung-Hyuk ; Park, Sang-Il ; Lyo, In-Woong ;
Journal of the Korean Society of Tribologists and Lubrication Engineers, volume 26, issue 6, 2010, Pages 311~316
Surface texturing of micro dimple or pore-shaped pattern was prepared using a fiber laser system. Surface texturing was designed to have a square pattern with a particular pitch distance for each corresponding density of 5, 10, 20, and 30%. Thermal damages such as bulges and burrs formed during laser irradiation were observed around the dimples. Thermal damages were later removed by lapping using alumina particles of
in diameter. Oscillating friction tests were performed against heat-treated high speed steels under lubricated condition. The lubricant used was SAE 5W-30 automotive engine oil. Normal contact pressure and oscillating frequency was 0.28 MPa and 20 Hz, respectively. The tests were continued for 20 minutes, and friction plots were recorded for examination. Results revealed that the coefficient of friction was lowered regardless of texturing density. Moreover, the lowest coefficient of friction was obtained for 10% density texturing. It is attributed to increased lubricity due to the introduction of surface texturing. In addition, it is concluded that the optimum texturing density and pattern must be found for the best lubricity and low friction.
Tin Sulphide Thin Films Formed by Sulphidising D.C. Magnetron Sputtered Layers of Tin Using
Leach, M. ; Jang, D.Y. ; Miles, R. ;
Journal of the Korean Society of Tribologists and Lubrication Engineers, volume 26, issue 6, 2010, Pages 317~321
Thin films of tin sulphide (SnS) have been formed by a novel 2-stage process where-in D.C. magnetron sputtering was used to deposit to thin films of tin (Sn) and the layers then sulphidised using 5% hydrogen sulphide (
) gas in Argon. Although it was not found possible to deposit high quality thin films of tin directly onto glass substrates, excellent layers of tin were produced by using molybdenum (Mo) coated glass as the substrate material. The chemical and physical properties of the SnS layers formed were determined using scanning electron microscopy, energy dispersive x-ray analysis, x-ray diffraction studies and using reflectance versus wavelength measurements and these related to the conditions of synthesis. The data shows that it should be possible to produce conventional "substrate structure" devices based on the use of this technology.
Performance Test of Inter-propellant Seal
Kwak, Hyun-D. ; Jeon, Seong-Min ; Kim, Jin-Han ;
Journal of the Korean Society of Tribologists and Lubrication Engineers, volume 26, issue 6, 2010, Pages 322~328
An inter-propellant seal (IPS) for 75 ton class thrust turbopump was tested. Leakage characteristics were presented with a given range of pressure difference under cryogenic as well as room temperature conditions. For cryogenic tests, liquid nitrogen was used as analogic fluid of liquid oxygen (LOX) while water was used instead of kerosene for room temperature condition. Test results showed that IPS had satisfactory leakage performance. Additionally endurance test was conducted to prove the life time of manufactured IPS and the tested IPS had successfully survived during required life time, 2100 seconds.
Prediction of Surface Roughness of Al7075 on End-Milling Working Conditions by Non-linear Regression Analysis
Cho, Yon-Sang ; Park, Heung-Sik ;
Journal of the Korean Society of Tribologists and Lubrication Engineers, volume 26, issue 6, 2010, Pages 329~335
Recently, the End-milling processing is needed the high-precise technique to get a good surface roughness and rapid time in manufacturing of precision machine parts and electronic parts. The optimum surface roughness has an effect on end-milling working condition such as, cutting direction, spindle speed, feed rate and depth of cut, and so on. It needs to form the correlation of working conditions and surface roughness. Therefore this study was carried out to presume of surface roughness on end-milling working condition of Al7075 by regression analysis. The results was shown that the coefficient of determination(
) of regression equation had a fine reliability of 87.5% and nonlinear regression equation of surface rough was made by multiple regression analysis.
The Nondestructive Reliability Evaluation which it Applies Ultrasound Thermography about Cutting Crack of Piston Skirt
Yang, Yong-Ha ; Ma, Sang-Dong ; Kim, Jea-Yeol ;
Journal of the Korean Society of Tribologists and Lubrication Engineers, volume 26, issue 6, 2010, Pages 336~340
Ultrasound thermography detects defects by radiating 20 ~ 30 kHz ultrasound waves to the samples and capturing the heat generated from the defects with the use of an infrared thermographic camera. This technology is being spotlighted as a next-generation NDE for the automobile and aerospace industries because it can test large areas and can detect defects such as cracks and exfoliations in real time. The heating mechanism of the ultrasound vibration has not been accurately determined, but the thermomechanical coupling effect and the surface or internal friction are estimated to be the main causes. When this heat is captured by an infrared thermographic camera, the defects inside or on the surface of objects can be quickly detected. Although this technology can construct a testing device relatively simply and can detect defects within a short time, there are no reliable data about the factors related to its detection ability. In this study, the ultrasound thermography technique was used to manufacture gasoline and diesel engine piston specimens, and nondestructive reliability tests to verify the applicability and validity of the ultrasound thermography technique.
The Research on NAUT Characteristics Evaluation by Defection Image
Na, Sun-Young ; Kim, Jae-Yeol ;
Journal of the Korean Society of Tribologists and Lubrication Engineers, volume 26, issue 6, 2010, Pages 341~345
The NAUT(Non contact Air coupled Ultrasonic Testing) is one of the ultrasonic wave inspection methods. It compensates High power ultrasound Pulser Receiver, pre-amp, air probe of high sensitivity in air to generate loss energy by NAUT methods. Generally, in case of ultrasound inspection, it applies contact methods by using couplant. However it can inspect of UT without couplant by this NAUT. The ultrasound transmission reception is composed in stable condition in NAUT. It can inspect high low material or the specimen of rough part, the narrow spot, too. The spot welding is applying the inosculation of automobile component, car body, all boards. The CFRP is necessity of NDE because of the solidity changes material according to lamella tearing. Therefore it checked on realization whether and commercialization in the spot welding and CFRP inspection that the NAUT would be applied them.