• Proceedings of the KWS Conference
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• 1996.10a
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• pp.186-190
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• 1996

Laser cladding is a technique for modification on surface in materials. This study describes a laser cladding equipment design and the results of laser cladding nickel on rolled steel for general structure. The laser clsdding equipment designed to consider continuous supply, a fixed quantity. The material used MC plastic. Laser cladding condition is found out by processing parameters. The experiment advanced to suppy substrate with powder. The substrate is rolled steel for general structure(KS D 3503) and powder is using the nickel powder for the corrosion resitance, wear resistance and surface hardness of materials. When the substrate travel on X-Y table, laser beam irradiates to prevent from oxidize with shielding gas on it. The obtained specimens measure the victors hardness test. For the research laser cladding results make a comparative study the microstructure.

• Proceedings of the KSME Conference
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• 2004.04a
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• pp.1120-1125
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• 2004

Welding characteristics of STS304 stainless steel and Inconel 600 using a continuous wave Nd:YAG laser are experimentally investigated. Alloy 600 being used in steam generator tubing of pressurized water reactor(PWR) exposed to some corrosion environment, stress corrosion cracking can occur on this material. Presented here are the results from a series of experiments in which dissimilar metal welds were made using the gas tungsten arc welding process with pure argon shielding gas. But It is well known that solidification cracking susceptibility of austenitic alloys depends on the solidification temperature range and amount/distribution of solute rich liquid that exists at the terminal stages of solidification. An experimental study was conducted to determine effects of welding parameters and to optimize those parameters that have the most influence on eliminating or reducing the extent welding zone formation at dissimilar metal welds.

• Proceedings of the KIEE Conference
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• 2005.07b
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• pp.1496-1499
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• 2005

This paper was represented an electrostatics distribution analysis using FEM(finite element method) with industrial type Inkjet plotter. Here, we know electronic value with each system position by experiment. these were decreased by discharge through earth and electricity shielding. According to industrial development, all fields using chemical instrument and material are generated an electrostatics. Based on these, the big large position of electrostatics was obtained metal base of controller, nonconductor fiber between two rubber roller, head controller by moving roller etc., Therefore these were showed an electrostatics generation source and by rubbing and meager profits electric charge.

• Transactions of Materials Processing
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• v.21 no.4
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• pp.221-227
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• 2012

The automotive and electronic industries have seriously considered the use of magnesium alloys because of their excellent properties such as strength to weight ratio, EMI shielding capability, etc. However, it is difficult to form magnesium alloys at room temperature because of the mechanical deformation related to twinning. Hence, magnesium alloys are normally formed at elevated temperatures. In this study, a temperature dependent constitutive model, the C-H/V model, for the magnesium alloy AZ31B sheet is proposed. A hardening law based on nonlinear kinematic and H/V(Hollomon/Voce) hardening model is used to properly characterize the Bauschinger effect and the stabilization of the flow stress. Material parameters were determined from a series of uni-axial cyclic experiments(C-T-C) with the temperature ranging between 150 and $250^{\circ}C$. The developed models are fit to experimental data and a comparison is made.

• Journal of the Korean Society for Precision Engineering
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• v.21 no.11
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• pp.53-60
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• 2004

Laser welding techniques have been characterised for various materials. In this paper, the laser weldability of STS304 stainless steel and Inconel 600 at dissimilar metal welds using a continuous wave Nd:YAG laser are experimentally investigated. Inconel 600 is being used in a steam generator tubing of pressurized water reactor(PWR) exposed to some corrosion. Stress corrosion cracking can occur on this material. An experimental study was conducted to determine effects of welding parameters, on eliminating or reducing the extent welding zone formation at dissimilar metal welds and to optimize those parameters that have the most influence parameters such as focus length, power, beam speed, shielding gas, and wave length of laser were tested.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.20 no.6
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• pp.17-25
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• 2021

In this study, the mechanical properties of railway-vehicle aluminum under frame was investigated based on the metal inert gas (MIG) welding conditions. An aluminum-alloy (6005A-T6) extruded material used in the lower panel of a railway vehicle was connected through MIG welding to determine the mechanical properties of MIG welds. Argon shielding gas and filler materials, such as ER5356 and ER4043, were used as consumable welding materials. For the welding conditions of the test specimen, welding frequencies of 2.5 and 4.5 Hz were applied using the SynchroPuls function, and the root faces were 1.0 and 1.5 mm. The mechanical properties of the MIG welds were determined through tensile, bending, and fatigue tests.

• Nuclear Engineering and Technology
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• v.53 no.6
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• pp.1887-1892
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• 2021

The effect of gadolinium and boron on the texture development and magnetic properties of the texture controlled 23Cr-10NiCu duplex stainless steels were studied to develop a high performance neutron and electromagnetic shielding material. The 23Cr-10NiCu base alloy is composed of 60% of austenite and 40% of ferrite, whereas, the 23Cr-10NiCu-0.5Gd-0.8B modified alloy is composed of 66% of austenite, 27% of ferrite and 7% of CrFeB intermetallic compounds. The gadolinium and boron addition to the 23Cr-10NiCu base alloy increased mechanical properties. Microstructure observation showed that the small addition of 0.5 wt% gadolinium and 0.8 wt% boron to the alloy retarded to form texture at the same hot rolling conditions, and improved the maximum magnetism, residual magnetism and coercive force about 3%, 122% and 120%, respectively.

• International conference on construction engineering and project management
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• 2007.03a
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• pp.41-49
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• 2007

GS E&C had developed construction management system, PMS which is based on EVMS in 1997. Recently, TPMS has developed for effective construction management through applying daily schedule management and JIT on materials, labors, equipments focusing field work. TPMS realizes "Shielding" and "Make-Ready Process" which are the main concept of Lean construction. Through this system, it can manage and plan daily field work, support the field work related material, labor, and equipment planning, and minimizes the non-valuable process. This paper introduces the concept of TPMS, and through established system, it can lead the construction culture and raise the competitive power of construction industry

• Proceedings of the Korean Institute of Building Construction Conference
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• 2020.06a
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• pp.191-192
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• 2020

The purpose of this study is to measure the electrical conductivity of cementitious composites as an early step to obtain shielding performance by mixing various type of steel fiber into cementitious composites, the main building material of protection facility, to shield electromagnetic pulse (EMP) damage. Fiber such as conductors as amorphous metallic fiber, hooked steel fiber, and smooth steel fiber are mixed into cementitious composites to give electrical conductivity and measure the impedance of concrete using LCR meter. By doing this, the electrical conductivity of each type of steel fiber reinforced cementitious composites (FRCC) is compared.

• Korean Journal of Materials Research
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• v.23 no.9
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• pp.501-509
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• 2013

To evaluate the development of the microstructure and mechanical properties on surface modified and post-heattreated Inconel 718 alloy, this study was carried out. A friction stir process as a surface modification method was employed, and overlap welded Inconel 718 alloy as an experimental material was selected. The friction stir process was carried out at a tool rotation speed of 200 rpm and tool down force of 19.6-39.2 kN; post-heat-treatment with two steps was carried out at $720^{\circ}C$ for 8 h and $620^{\circ}C$ for 6 h in vacuum. To prevent the surface oxidation of the specimen, the method of using argon gas as shielding was utilized during the friction stir process. As a result, applying the friction stir process was effective to develop the grain refinement accompanied by dynamic recrystallization, which resulted in enhanced mechanical properties as compared to the overlap welded material. Furthermore, the post-heat-treatment after the friction stir process accelerated the formation of precipitates, such as gamma prime (${\gamma}^{\prime}$) and MC carbides, which led to the significant improvement of mechanical properties. Consequently, the microhardness, yield, and tensile strengths of the post-heat-treated material were increased more than 110%, 124% and 85 %, respectively, relative to the overlap welded material. This study systematically examined the relationship between precipitates and mechanical properties.