• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2009.11a
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• pp.453-456
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• 2009

Impact resistance of shape memory alloy hybrid composite(SMAHC) plates were experimentally investigated. Shape memory alloy(SMA) have large failure strain and failure stress and can absorb large strain energies through phase transformation. SMA wires were embedded in composite plates to improve their weak impact resistance. Tensile tests of SMA wires were performed at various temperature to investigate their thermo-mechanical properties. Low-Velocity impact tests of several types of composite plates with SMA/Al/Fe were performed. Embedding SMA wires was most effective to improve impact resistance of composite plates. The effects of SMA position on impact resistance were also investigated.

• Journal of the Korean Ceramic Society
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• v.35 no.9
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• pp.939-944
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• 1998

The formation microstructure and properties of novel ceramic composite materials by active filler con-trolled polymer pyrolysis were investigated. Polymethlsiloxane filled with W is of particular interested be-cause of the formation of ceramic bonded hard materials (WC-$W_{2}C$-$S_{1}OC$) for wear resistant applications. Highly metal-filled polymer suspensions were prepared and their conversion to ceramic composites by an-nealing in $N_{2}C$ atmosphere at 1000-$1600^{\circ}C$ were studied. Dimensional change porosity and phase distribution (filler network) were analyzed and correlated to the resulting material properties. Microcrystalline com-posites with the filler reaction products embedded to the resulting material properties. Microcrystalline com-posites with the filler reaction products embedded in a silicon oxycarbide glass matrix were produced. De-pending on the pyrolysis conditions ceramic composites with a density up to 95 TD% a hardness of 7-8.8GPa Yong's modulus of 220-230 GPa a fracture toughness of 6-6.8$MPam^{1/2}$ and a flexual strength of 380-470 MPa were obtained.

• Journal of the korean academy of Pediatric Dentistry
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• v.23 no.2
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• pp.450-460
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• 1996

The purpose of this study was to compare shear bond strength of composite resin using several dentin bonding agents and light cured glass ionomer cement(Fuji II LC). 40 Bovine primary anterior teeth were used for this experiment. Labial surface of teeth were flattened. It were divided into four groups. Each group was composed of 10 teeth. The material used for this experiment were Scotchbond Multipurpose-Z-100, Allbond 2-Aelitefil, Gluma-Pekalux, light cured glass ionomer cement(Fuji II LC). Each of the materials was applied to the exposed surfaces of 10 teeth by insertion into a cylindrical shaped matrix which is 3mm diameter and 3mm in height. The completed specimens were stored at $37^{\circ}C$ under 100% humidity for 24 hours : the shear bond strength of each material to dentin surface were measured with INSTRON universal testing machine. The results were as follows : 1. Shear bond strength to dentin surface increased in order of light cured glass ionomer cement(Fuji II LC), Gluma, Allbond 2, Scotchbond Multipurpose. 2. Between shear bond strength of light cured glass ionomer cement(Fuji II LC) and Allbond 2, there was statistical significace(p<0.05) 3. Between shear bond strength of light cured glass ionomer cement(Fuji II LC) and Scotchbond Multipurpose, between shear bond strength of Gluma and Scotchbond Multipurpose, there was statistical significance.(p<0.01) The shear bond strength of dentin bonding agents were higher than light cured glass ionomer cement. The reason is that materials and quality of dentin bonding agent were enhanced. Further investigation is necessary to improve shear bond strength of light cured glass ionomer cement.