• KSTLE International Journal
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• 제7권2호
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• pp.51-55
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• 2006

In order to design an effective foot surface which can provide adequate friction for a self-propelled medical microrobot moving inside the small intestine, frictional mechanisms between the small intestine inner wall and the foot surface of the robot must be understood. In this paper, mechanical interlocking effect was considered to design the surface of the foot that can generate the desired frictional force. The concept of the design was derived from the hookworm that lives inside the small intestine. Hookwarms are known to adhere to the small intestine wall by interlocking with villi on the surface of the small intestine. The interlocking mechanism was considered as the main frictional mechanism for the design of the microrobot foot surface in this work. 2 mm and 6 mm diameter solid and hollow cylindrical shaped foot specimens were designed and tested to assess the frictional force between the specimens and the porcine small intestine specimen.

• Computers and Concrete
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• 제23권2호
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• pp.97-106
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• 2019

This paper describes the design of a new interlocking masonry system, the production of designed interlocking units and mechanical properties of interlocked masonry assemblages with mortar. In this proposed system, units have horizontal and vertical locks to integrate the units to the wall and have a channel to enable the use of horizontal reinforcements in the wall. Using these units, unfilled, filled or reinforced walls can be constructed with or without mortar. In the production of the interlocking units, it was decided to use foamed concrete. 12 trial productions have been carried out at different mix proportions to obtain the optimum concrete mix. At the end of the mentioned productions, the units were produced with foam concrete which is selected as the most suitable in terms of compressive strength and specific gravity. Then, axial compression, diagonal tension and bed joint shear tests were carried out to determine the mechanical properties of the interlocked masonry assemblages with mortar. Results from the tests showed that interlocks designed to strengthen the system against shear stresses by creating discontinuity throughout the joints have been successful to achieve their aim. Obtained data will enable structural analysis of walls to be constructed with these new units.

• 한국기계가공학회지
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• 제21권2호
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• pp.87-93
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• 2022

The demand for metal-polymer joining technology have been increasing, especially in the industrial fields of automotive and aerospace, which require the manufacturing of various lightweight parts. Conventional joining processes have technical hurdles on aspects such as thermal degradation, need for chemical surface treatment, or complicated process settings. These issues can be alleviated by employing interlocking structures for the metal-polymer joined interface. In this study, we joined 3D-printed metal and polymer parts, which were featured with 3D-printed interlocking structures at their interface. By using high frequency induction heating, the joined region could be locally heated to reduce the thermal degradation and distortion of polymer parts. In addition, through the adjustment of interface morphologies and compression conditions, the polymer flow could be optimized to completely fill the interlocking grooves on metal parts, thereby achieving high joining strength. This suggests feasible guidelines for manufacturing metal-polymer joined structures involving 3D-printed architectures.

• 한국표면공학회지
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• 제36권4호
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• pp.347-355
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• 2003

Roughening of metal surfaces frequently enhances the adhesion strength of metals to polymers by mechanical interlocking. When a failure occurs at a roughened metal/polymer interface, the failure prone to be cohesive. In a previous work, an adhesion study on a roughened metal (oxidized copper-based leadframe)/polymer (Epoxy Molding Compound, EMC) interface was carried out, and the correlation between adhesion strength and failure path was investigated. In the present work, an attempt to interpret the failure path was made under the assumption that microvoids are formed in the EMC as well as near the roots of the CuO needles during compression-molding process. A simple adhesion model developed from the theory of fiber reinforcement of composite materials was introduced to explain the adhesion behavior of the oxidized copper-based leadframe/EMC interface and failure path. It is believed that this adhesion model can be used to explain the adhesion behavior of other similarly roughened metal/polymer interfaces.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2004년도 추계 학술발표회 제16권2호
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• pp.469-472
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• 2004

This paper presents test results to prevent debonding failure of reinforced concrete beams strengthened with near-surface mounted(NSM) CFRP. Beams strengthened with different strengthening systems with externally bonded CFRP, NSM CFRP and NSM CFRP with mechanical interlocking. Test results indicated that using NSM CFRP is improved the stiffness and increased the flexural capacity of RC beams and NSM CFRP with mechanical interlocking prevented debonding failure of RC beams.

• 대한치과보철학회지
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• 제18권1호
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• pp.49-57
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• 1980

The adhesive mechanisms on the metal-ceramic restorations have been reported to be mechanical interlocking, chemical bonding, compressive force, and Van der Waal's force, etc. Of these, the mechanical interlocking and chemical bonding forces are thought to affect the adhesive force between Ni-Cr alloy and porcelain. This study investigates the adhesion of Ni-Cr alloy to porcelain according to surface treatment. For this purpose, the following experiments were made; The compositions of Ni-Cr alloy as cast by emission spectrograph, and the oxides produced on Ni-Cr alloy during degassing at $1850^{\circ}F$ for 30 minutes in air and in vacuum were analyzed by X-ray diffractograph. The metal phases of Ni-Cr alloy were observed according to porcelain-baking cyclic heat treatment by photo microscope and the distribution and the shift of elements of Ni-Cr alloy and porcelain and the failure phases between Ni-Cr alloy and porcelain by scanning electron microscope. The adhesive force between Ni-Cr alloy and porcelain was measured according to surface treatment with oxidization and roughening by Instron Universal Testing Machine. Results were as follows; 1. The metal phases of Ni-Cr alloy as cast and degassing state showed the enlarged and fused core, but when subjected to porcelain-baking cyclic heat treatment, showed a dendrite growing. 2. The kinds of metal oxides produced on Ni-Cr alloy during degassing were found to be NiO and $Cr_2O_3$. 3. The distribution of elements at the interface of Ni-Cr alloy and porcelain in degassing state showed demarcation line, but in roughening state, showed mechanical interlocking phase. 4. The shift of elements at the interface occurred in both states, but the shift amount was found to be larger in roughening than in degassing. 5. The adhesive force between Ni-Cr alloy and porcelain was found to be $3.45{\pm}0.93kg/mm^2$, in degassing and $3.82{\pm}0.99kg/mm^2$, in roughening. 6. The failure phase between Ni-Cr alloy and porcelain showed the mixed type failure.

• 한국섬유공학회:학술대회논문집
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• 한국섬유공학회 1998년도 가을 학술발표회논문집
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• pp.33-36
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• 1998

Segmented block copolyetheresters defined as copolymers having sequences of alternating polyester hard blocks and polyether soft blocks create labile physical cross-links upon crystallization of hard polyester blocks Since the nature of the physical interlocking is a crystallite formed exclusively from the crystallizable hard segment, the hard segment content (HSC) and hard segment length (HSL) will play an important role in determining the properties such as mechanical property and dynamic mechanical property. (omitted)

• 한국세라믹학회지
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• 제24권3호
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• pp.223-226
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• 1987

Among many densification routes for silicon nitride, HIP(hot isostatic pressing) is becomming more popular these days, mainly due to the fact that it can produce highly reliable products with superior mechanical properties. This study involves in sintering of silicon nitride followed by HIP which requires no canning. Various property changes curing sintering and HIP are observed and analyzed in terms of microstructural changes. Porosity decrease and enhanced interlocking of grains by HIP are considered to be the major causes for improved mechanical properties of silicon nitride.

• 한국세라믹학회지
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• 제19권2호
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• pp.121-126
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• 1982

This paper deals with the $Si_3N_4$-bonded SiC refractory in terms of its microstructure development during nitridation. When mixture of SiC grains and fine Si power is fired under nitrogen atmosphere, an interlocking network of $Si_3N_4$ whiskers is formed by nitridation of Si. It is found that the strength of $Si_3N_4$-bonded SiC refractory is soley due to the physical nature of this interlocking whiskers. At the initial stage of nitridation, $Si_3N_4$ whisker forms in very thin and long shape and, with further nitridation, it becomes thicker with diameters up to 0.35$\mu\textrm{m}$. It is found that the mechanical strength of $Si_3N_4$-bonded SiC refractory depends on the degree of nitridation and the development of microstructure.

• 대한금속재료학회지
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• 제48권6호
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• pp.557-564
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• 2010

Formation of Sn through-silicon-via (TSV) and its interconnection processes were studied in order to form a three-dimensional interconnection structure of chip-stack packages. Different from the conventional formation of Cu TSVs, which require a complicated Cu electroplating process, Sn TSVs can be formed easily by Sn electroplating and reflow. Sn via-filling behavior did not depend on the shape of the Sn electroplated layer, allowing a much wider process window for the formation of Sn TSVs compared to the conventional Cu TSV process. Interlocking joints were processed by intercalation of Cu bumps into Sn vias to form interconnections between chips with Sn TSVs, and the mechanical integrity of the interlocking joints was evaluated with a die shear test.