• Composites Research
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• v.25 no.5
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• pp.154-158
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• 2012

The effect of structure on the sound absorption and sound transmission loss of composite sheet was investigated. A sheet of polypropylene was bonded by hot press with nonwoven fabric sheets of polyethylene terephthalate on the top side and the back side. Absorption coefficient of composite sheet using nonwoven fabric with surface density of $0.64kg/m^2$ was 0.1-0.2. It is 100-400% improvement compare to that of polypropylene sheet. The transmission loss of composite sheet was increased with surface density of polypropylene board and introduction of hemisphere hole on the surface of sheet. Two types of composite sheet were made using flat sheet and sine wave shaped sheet and the effect of sheet structure on the transmission loss was investigated.

• Design & Manufacturing
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• v.6 no.1
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• pp.95-100
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• 2012

In this study, a novel Cu composite sheet with embedded high electric conduction path was developed as another alternative for the interconnect materials possessing high electrical conductivity as well as high strength. The Cu composite sheet was fabricated by forming Ag conduction paths not within the interior but on the surface of a high strength Cu substrate by damascene electroplating process. As a result, the electrical conductivity increased by 40% thanks to mesh type Ag conduction paths, while the ultimate tensile strength decreased by 20%. The interfacial fracture resistance of Cu composite sheet prepared by damascene electroplating increased by above 50 times compared to Cu composite sheet by conventional electroplating. For feasibility test for practical application, a leadframe for LED module was manufactured by a progressive blanking and piercing processes, and the blanked surface profile was evaluated as a function of the volume fraction of Ag conduction paths. As Ag conduction path became finer, pressing formability improved.

• Proceedings of the Korea Committee for Ocean Resources and Engineering Conference
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• 2000.04a
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• pp.157-163
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• 2000

The application as the parts of an automobile, using the property of GMT-Sheet, is increasing. In order to exchange the parts of an automobile for GMT-Sheet, at first, the establishment and joining problem of exact joining strength must be determined. We have studied it using composites which is not same each other fiber oriented condition so as to determine joining strength and joining condition of GMT-Sheet. In this study, the result of experiment of forming condition concerned joining problem of GMT-Sheet is this ; joining efficiency of GMT-Sheet, increases as lap joint length L increases. Increase of compression ration cause decrease of joining efficiency after of GMT-Sheet, joining. In the viewpoint of recycling, randomly oriented composite of GMT-Sheet is desirable more than unidirectional oriented composite. We have better design the structure so as not occur to stress centralization on the joining part.

• 제어로봇시스템학회:학술대회논문집
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• 2000.10a
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• pp.553-553
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• 2000

The application as the parts of an automobile, using the property of GMT-Sheet, is increasing. In order to exchange the parts of an automobile for GMT-Sheet, at first, the establishment and joining problem of exact joining strength must be determined. We have studied it using composites which is not same each other fiber oriented condition so as to determine joining strength and joining condition of GMT-Sheet. h this study, the result of experiment of forming condition concerned joining problem of GMT-Sheet is this ; joining efficiency of of GMT-Sheet, increases as lap joint length L increases. Increase of compression ratio causes decrease of joining efficiency after of GMT-Sheet joining. In the viewpoint of recycling, randomly oriented composite of GMT-Sheet is desirable more than unidirectional oriented composite. We has better design the structure so as not to occur to stress centralizatien on the joining part.

• Journal of Ocean Engineering and Technology
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• v.15 no.2
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• pp.111-119
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• 2001

The application as the parts of an automobile, using the property of GMT-Sheet, is increasing. In order to exchange the parts of an automobile for GMT-Sheet, at first, the establishment and problem of exact joining strength must be determined. We have studied it using composites which is not same each other fiber oriented condition so as to determine joining strength and joining condition of GMT-Sheet. In this study, the result of experiment of forming condition concerned joining problem of GMT-Sheet is this; joining efficiency of GMT-Sheet, increases as lap joint length L increases. Increase of compression ratio causes decrease of joining efficiency after of GMT-Sheet joining. In the viewpoint of recycling, randomly oriented composite of GMT-Sheet is desirable more than unidirectional oriented composite. We has better design the structure so as not to occur to stress centralization on the joining part.

• Korean Journal of Materials Research
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• v.12 no.11
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• pp.883-888
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• 2002

We investigated the void formation in composite-titanium silicide($TiSi_2$) process. We varied the process conditions of polycrystalline/amorphous silicon substrate, composite $TiSi_2$ deposition temperature, and silicidation annealing temperature. We report that the main reason for void formation is the mass transport flux discrepancy of amorphous silicon substrate and titanium in composite layer. Sheet resistance in composite $TiSi_2$ without patterns is mainly affected by silicidation rapid thermal annealing (RTA) temperature. In addition, sheet resistance does not depend on the void defect density. Sheet resistance with sub-0.5 $\mu\textrm{m}$ patterns increase abnormally above $850^{\circ}C$ due to agglomeration. Our results imply that $sub-750^{\circ}C$ annealing is appropriate for sub 0.5 $\mu\textrm{m}$ composite X$sub-750_2$ process.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2014.11a
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• pp.163-164
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• 2014

This study is conducted for prevent spread of penetration water and water leakage through non-woven fabric between PVC sheet and PVC sheet in the PVC composite waterproofing sheet of a multi-layer structure. For this, carry out absorption amount test to confirm spread resistance performance after manufacturing PVC composite waterproofing sheet of a multi-layer structure using water-repellency processed non-woven fabric. As a result of test, weight of water-repellency processed non-woven fabric increased to 1.178g, Compared with beginning and there are not penetration water.

• Steel and Composite Structures
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• v.23 no.3
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• pp.351-362
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• 2017

This paper presents an experimental study on the behavior of composite floor slab comprised by a new steel sheet and concrete slab. The strength of composite slabs depends mainly on the strength of the connection between the steel sheet and concrete, which is denoted by longitudinal shear strength. The composite slabs have three main failures modes, failure by bending, vertical shear failure and longitudinal shear failure. These modes are based on the load versus deflection curves that are obtained in bending tests. The longitudinal shear failure is brittle due to the mechanical connection was not capable of transferring the shear force until the failure by bending occurs. The vertical shear failure is observed in slabs with short span, large heights and high concentrated loads subjected near the supports. In order to analyze the behavior of the composite slab with a new steel sheet, six bending tests were undertaken aiming to provide information on their longitudinal shear strength, and to assess the failure mechanisms of the proposed connections. Two groups of slabs were tested, one with 3000 mm in length and other with 1500 mm in length. The tested composite slabs showed satisfactory composite behavior and longitudinal shear resistance, as good as well, the analysis confirmed that the developed sheet is suitable for use in composite structures without damage to the global behavior.

• Current Research on Agriculture and Life Sciences
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• v.27
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• pp.29-33
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• 2009

Liquefied-wood polymer composite was prepared and mechanical properties was evaluated to develop potential utility of liquefied wood. The liquefied wood was made from waste wood and chemical modified with acetic anhydride and maleic anhydride (MA), phtalic anhydride (PA). The composite sheet was prepared from modified liquefied-wood and polymer(PE). The mechanical, chemical and microscopical properties composite sheet were investigated. The results were summarized as follows, 1. The tensile strength was increased and breaking elongation of composite sheet was decreased with the time of acetylation and the dosage of MA. 2. The Young's modulus of composite sheet was gradually decreased with the dosage of PA. 3. The peak intensity of 1737cm-1 in FT-IR spectra of chemical modified liquefied woods was increased. 4. The dispersity of liquefied woods with PE was improved with chemical modification.

• Steel and Composite Structures
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• v.21 no.6
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• pp.1307-1325
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• 2016

Nonlinear behavior of two-span, continuous composite steel-concrete girders strengthened with Carbon Fiber Reinforced Polymers (CFRP) bonded to the top of concrete slab over the negative moment region was evaluated using a non-linear Finite Element (FE) model in this paper. A three-dimensional FE model of continuous composite girder using commercial software ABAQUS simulated and validated with experimental results. The interfacial regions of the composite girder components were modeled using suitable interface elements. Validation of the proposed numerical model with experimental data confirmed the applicability of this model to predict the loading history, strain level for the different components and concrete-steel relative slip. The FE model captured the different modes of failure for the continuous composite girder either in the concrete slab or at the interfacial region between CFRP sheet and concrete slab. Through a parametric study, the thickness of CFRP sheet and shear connection required to develop full capacity of the continuous composite girder at negative moment zone have been investigated. The FE results showed that the proper thickness of CFRP sheet at negative moment region is a function of the adhesive strength and the positive moment capacity of the composite section. The shear connection required at the negative moment zone depends on CFRP sheet's tensile stress level at ultimate load.