Go to the main menu
Skip to content
Go to bottom
REFERENCE LINKING PLATFORM OF KOREA S&T JOURNALS
> Journal Vol & Issue
Journal Basic Information
Journal DOI :
The Korean Society for Composite Materials
Editor in Chief :
Volume & Issues
Volume 27, Issue 6 - Dec 2014
Volume 27, Issue 5 - Oct 2014
Volume 27, Issue 4 - Aug 2014
Volume 27, Issue 3 - Jun 2014
Volume 27, Issue 2 - Apr 2014
Volume 27, Issue 1 - Feb 2014
Selecting the target year
Review of the Research and Development of Ceramic Matrix Composite Materials and Future Works
Lee, Tae Ho ;
Composites Research, volume 27, issue 4, 2014, Pages 123~129
DOI : 10.7234/composres.2014.27.4.123
Ceramic matrix composites (CMCs) consist of such reinforcements as carbides, nitrides, borides and oxides, which have high melting points, low density, high modulus and high strength, for the purpose of increasing toughness. These materials are used for heat shielding systems for aerospace vehicles, high-temperature gas turbine combustion chambers, turbine blades, stator vane parts, etc. Oxide CMCs are used for the components of burner and flame holder and the high-temperature gas duct. CMCs are also applied to brake disks, which are subjected to severe thermal shock, and slide bearing parts under heavy loads. The research and development of the CMC are progressed for the strategic purpose in defense and energy industry; for instance, for aerospace applications in the U.S., and for hyper-speed aircraft, gas turbines, and atomic fissions in U.S., Japan, and Europe.
A Constitutive Equation Including Strain Rate Effect for the Expanded Polypropylene
Kim, Han-Kook ; Cheon, Seong S. ;
Composites Research, volume 27, issue 4, 2014, Pages 130~134
DOI : 10.7234/composres.2014.27.4.130
The purpose of this paper is to build DB in order to Propose new constitutive equations by redefining constitutive equations for Polyurethane presented by Jeong et al.  based on Quasi-static test and Impact test DB of Expanded polypropylene using cylindrical specimens with 4 different densities presentsd by Kim et al.  for EPP foam and combining the impulse-momentum theory.
Application of the EPU Constitutive Equation to expanded Polypropylene under Dynamic Loading
Jeong, Kwang Young ; Kim, Byeong-Jun ; Cheon, Seong S. ;
Composites Research, volume 27, issue 4, 2014, Pages 135~140
DOI : 10.7234/composres.2014.27.4.135
A constitutive equation, which was suggested for describing the compressive deformation behaviour of the expanded polyurethane, was applied to the expanded polypropylene under dynamic loading. This equation consists of seven parameters, five of which are obtained by fitting the stress strain curve obtained from the quasi-static compression test at the lowest base strain rate. The remaining two parameters are able to be determined by fitting the curve from the compression test at different two stage strain rates. In order to check the eligibility of the equation at high strain rate, the impact test was performed and the results were compared to the analytical constitutive equation results for the expanded polypropylene with expansion ratios of 30 and 40 times, respectively.
Impact Signal Monitoring of a Composite Structure Using Piezoelectric Paint Sensor
Park, Seung-Bok ; Han, Dae-Hyun ; Kang, Lae-Hyong ;
Composites Research, volume 27, issue 4, 2014, Pages 141~145
DOI : 10.7234/composres.2014.27.4.141
This paper presents a structural health monitoring method using piezoelectric paint sensor designed for an impact sensor. The piezoelectric paint sensor can be flexibly deposited onto most structural surfaces in a thin form of the paint, and measure impact signals without any external device such as a power amplifier. In this study, a composite plate having four zones coated with piezoelectric paint was used for impact monitoring test. The sensitivity of the piezoelectric paint sensor was obtained by measuring the output voltages against the impact force. In addition to the sensitivity measurement, the impact position has been also estimated by comparing the output signals of the paint sensors when the impact occurs on the specimen.
Sensitivity Measurement of the Piezoelectric Paint Sensor according to the Poling Electric Field
Han, Dae-Hyun ; Park, Seung-Bok ; Kang, Lae-Hyong ;
Composites Research, volume 27, issue 4, 2014, Pages 146~151
DOI : 10.7234/composres.2014.27.4.146
In this study, the experimental study has been performed by varying the polarization of the electric field and impact force to check the piezoelectric characteristics of piezoelectric paint sensor. Piezoelectric paint sensor used in this study is composed of epoxy resin with a hardener and PNN-PZT powder in 1:1 weight ratio. The dimensions of the paint sensor specimen are
and regular specimens were made using a mold. The voids are removed from the specimen in the vacuum desiccator. Both upper side and bottom side of the paint sensor were coated with silver paste for making an electrode and then dried at room temperature for a day. The poling treatment has been carried out under controlled conditions of the electric field in order to check the effect of piezoelectric sensitivities, while the poling temperature was fixed at room temperature and the poling time was set to 30 min. The piezoelectric sensitivities have been measured by comparing output voltage from paint sensor with output force from impact hammer when the impact hammer hits the paint sensor. In result, the effect of the electric field has been evaluated for the sensitivity and describe the result.
Composite Fracture Detection Capabilities of FBG Sensor and AE Sensor
Kim, Cheol-Hwan ; Choi, Jin-Ho ; Kweon, Jin-Hwe ;
Composites Research, volume 27, issue 4, 2014, Pages 152~157
DOI : 10.7234/composres.2014.27.4.152
Non-destructive testing methods of composite materials are very important for improving material reliability and safety. AE measurement is based on the detection of microscopic surface movements from stress waves in a material during the fracture process. The examination of AE is a useful tool for the sensitive detection and location of active damage in polymer and composite materials. FBG (Fiber Bragg Grating) sensors have attracted much interest owing to the important advantages of optical fiber sensing. Compared to conventional electronic sensors, fiber-optical sensors are known for their high resolution and high accuracy. Furthermore, they offer important advantages such as immunity to electromagnetic interference, and electrically passive operation. In this paper, the crack detection capability of AE (Acoustic Emission) measurement was compared with that of an FBG sensor under tensile testing and buckling test of composite materials. The AE signals of the PVDF sensor were measured and an AE signal analyzer, which had a low pass filter and a resonance filter, was designed and fabricated. Also, the wavelength variation of the FBG sensor was measured and its strain was calculated. Calculated strains were compared with those determined by finite element analysis.
Design and Verification of Shear Buckling Test Fixture for Composite Laminate
Park, Sung-Jun ; Ko, Myung-Gyun ; Kim, Dong-Gwan ; Kim, Sang-Kuk ; Moon, Chang-Oh ; Kweon, Jin-Hwe ; Choi, Jin-Ho ;
Composites Research, volume 27, issue 4, 2014, Pages 158~167
DOI : 10.7234/composres.2014.27.4.158
Final goal of this research is to establish the database for correlation factors which connects the test and analysis results of shear buckling allowables for composite plate. To accomplish the goal, extensive test and analysis works are required. In this paper, as the first step, a frame-type fixture for shear buckling test was designed and validated through the test and analysis. Final configuration of the fixture were determined via parametric study on the effect of specimen size, cross-sectional dimensions, and number of fastening bolts on the shear buckling load. Results of the study showed the designed frame-type fixture successfully induces the shear buckling of composite plate. However, there were deviations between the test results and analysis results for ideal case under pure shear load, which were mainly caused by the difference in plate sizes for both cases. The difference were larger in the plates with larger hole and simply supported boundary condition. It is concluded from the results that while the designed fixture can be used for the clamped plates with acceptable accuracy, it shows larger difference in the simply supported plates.
Optimum Mixing Ratio of Epoxy for Glass Fiber Reinforced Composites with High Thermal Stability
Shin, Pyeong-Su ; Wang, Zuo-Jia ; Kwon, Dong-Jun ; Choi, Jin-Yeong ; Sung, Ill ; Jin, Dal-Saem ; Kang, Suk-Won ; Kim, Jeong-Cheol ; Park, Joung-Man ;
Composites Research, volume 27, issue 4, 2014, Pages 168~173
DOI : 10.7234/composres.2014.27.4.168
The optimum condition of glass fiber/epoxy composites was investigated according to mixing ratio of two epoxy matrices. Novolac type epoxy and isocyanate modified epoxy were used as composites matrix. Based on chemical composition of mixing matrix, optimum mixing ratio of epoxy resins was obtained through various experiments. In order to investigate thermal stability and interface of epoxy resin, glass transition temperature was observed by DSC instrument, and static contact angle was measured by reflecting microscope. Change of IR peak and
was conformed according to different epoxy mixing ratio. After fabrication of glass fiber/epoxy composites, tensile, compression, and flexural properties were tested by UTM by room and high temperature. The composites exhibited best mechanical properties when epoxy mixing ratio was 1:1.
Analysis of Thermal Deformation of Carbon-fiber Reinforced Polymer Matrix Composite Considering Viscoelasticity
Jung, Sung-Rok ; Kim, Wie-Dae ; Kim, Jae-Hak ;
Composites Research, volume 27, issue 4, 2014, Pages 174~181
DOI : 10.7234/composres.2014.27.4.174
This study describes viscoelasticity analysis of carbon-fiber reinforced polymer matrix composite material. One of the most important problem during high temperature molding process is residual stress. Residual stress can cause warpage and cracks which can lead to serious defects of the final product. For the difference in thermal expansion coefficient and change of resin property during curing, it is difficult to predict the final deformed shape of carbon-fiber reinforced polymer matrix composite. The consideration of chemical shrinkage can reduce the prediction errors. For this reason, this study includes the viscoelasticity and chemical shrinkage effects in FE analysis by creating subroutines in ABAQUS. Analysis results are compared with other researches to verify the validity of the subroutine developed, and several stacking sequences are introduced to compare tested results.