Wyniki wyszukiwania - BazTech

1

Effect of Electroless Ni–P Plating on the Bonding Strength of Bi–Te-Based Thermoelectric Modules

Kim S. S., Son I., Kim K. T.

Archives of Metallurgy and Materials

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2017

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Vol. 62, iss. 2B

1225--1229

EN

In the present study, electroless Ni–P plating was applied to Bi–Te-based thermoelectric materials as a barrier layer and the effect of the Ni–P plating on the bonding strength of the thermoelectric module was investigated. The bonding strength of the n- and p-type modules increased after being subjected to the electroless Ni–P plating treatment. In the case of the thermoelectric module that was not subjected to electroless Ni–P plating, Sn and Te were interdiffused and formed a brittle Sn–Te-based metallic compound. The shearing mostly occurred on the bonding interface where such an intermetallic compound was formed. On the other hands, it was found from the FE-EPMA analysis of the bonding interface of thermoelectric module subjected to electroless Ni-P plating that the electroless Ni-P plating acted as an anti-diffusion layer, preventing the interdiffusion of Sn and Te. Therefore, by forming such an anti-diffusion layer on the surface of the Bi–Te based thermoelectric element, the bonding strength of the thermoelectric module could be increased.

2

Experimental Study On Fracture Property Of Tapered Double Cantilever Beam Specimen With Aluminum Foam

Kim Y. C., Kim S. S., Cho J. U.

Archives of Metallurgy and Materials

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2015

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Vol. 60, iss. 2B

1459--1462

EN

It is indispensable to evaluate fracture energy as the bonding strength of adhesive at composite material with aluminum foam. This specimen is designed with tapered double cantilever beam by British standards (BS 7991 and ISO 11343). 4 kinds of specimens due to m values of 2, 2.5, 3 and 3.5 are manufactured and compared each other with the experimental results. Adhesive fracture energy is calculated from the formulae of British standards. The value of m is the gradient which is denoted as the length and the height of specimen. As m becomes greater at static experimental result, the maximum load becomes higher and the displacement becomes lower. And the critical fracture energy becomes higher. As m becomes less at fatigue experimental result, the displacement becomes higher and the critical fracture energy becomes higher. Fracture behavior of adhesive can be analyzed by this study and these experimental results can be applied into real field effectively. The stability on TDCB structure bonded with aluminum foam composite can be predicted by use of this experimental result. Adhesive fracture energy is calculated from the formulae of British standards. Based on correlations obtained in this study, the fracture behavior of bonded material would possibly be analyzed and aluminum foam material bonded with adhesive would be applied to a composite structure in various fields, thereby analyzing the mechanical and fracture characteristic of the material.

3

Nowa technologia aktywacji granulowanego żużla wielkopiecowego za pomocą wody z produkcji betonu towarowego

Ryou J. S., Song II. H., Kim S. S., Lee J. B.

Cement Wapno Beton

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2013

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R. 18/80, nr 1

33--38

PL

W pracy przedstawiono doświadczalne wyniki aktywacji granulowanego żużla wielkopiecowego za pomocą odpadowej wody z produkcji betonu towarowego. Wykazano, że ten odpad ma pH większe od 12 i jako woda zarobowa może stanowić dobry aktywator żużla. Wytrzymałość na ściskanie zapraw żużlowych zwiększała się wraz ze wzrostem zawartości fazy stałej w tej odpadowej wodzie, w całym objętym doświadczeniami zakresie od 1% do 10%. Natomiast skurcz suszenia był taki sam jak porównawczej zaprawy z cementu portlandzkiego tylko do zawartości fazy stałej wynoszącej 3%. W przypadku wyższych zawartości, to jest 5%, 7% i 10%, był znacznie większy. Biorąc to pod uwagę autorzy proponują stosować jako aktywator wodę odpadową zawierającą maksymalnie 3% fazy stałej.

EN

The work presents the results of granulated blastfurnace slag activation with recycling water from ready-mixed concrete production. It was shown that this water has high pH level and used as mixing water is a good activator for slag. The compressive strength of mortars was increasing with the content of solid phase in this water, and in examined samples ranged from 1% to 10%. The drying shrinkage of mortars were close to the reference mortar from Portland cement until 3% of solid phase content in recycled water. However, if solid phase content was higher, namely 5%, 7% and 10% the shrinkage was much higher. Taking this mortar behavior into consideration, according the authors only recycled water containing up to 3% of solid phase can be used as slag activator.

4

Superadditivity and monotonicity of Gram's determinants in 2-inner product spaces and their applications

Kim S. S., Dragomir S. S., Cho Y. J.

Demonstratio Mathematica

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2003

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Vol. 36, nr 4

807--817

EN

In this paper, we shall give some properties of superadditivity and mono-tonicity of Gram's determinants in 2-inner product spaces and their applications.

5

Nordsieck form of multirate integration method for flexible multibody dynamic analysis

Kim S. S.

Computer Assisted Mechanics and Engineering Sciences

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2002

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Vol. 9, No. 3

391-403

EN

A Nordsieck form of multirate integration scheme has been proposed for flexible multibody dynamic systems of which motions are represented by large gross motion coupled with small vibration. Based on the conventional flexible multibody dynamics formulation, vibrational modal coordinates with floating reference frame and relative joint coordinates are employed to describe the motion in this research. In the multirate integration, the fast variables of the flexible multibody system are integrated with smaller stepsize, whereas the slow variables are integrated with larger stepsize. It is assumed that vibrational modal coordinates are treated as fast variables, whereas the relative joint coordinates are treated as slow variables to apply multirate integration method. A method that decomposes the equations of motion for flexible multibody systems into a fast system with flexible coordinates and a slow system with joint relative coordinates has been also proposed. The proposed multirate integration method is based on the Adams-Bashforth-Moulton predictor-corrector method and implemented in the Nordsieck vector form. The Nordsieck form of multirate integration method provides effective step-size control and at the same time, inherits the efficiency from the Adams integration method. Simulations of a flexible gun and turret system of a military tank have been carried out to show the effectiveness and efficiency of the proposed method.