A5101615920- Advanced Welding Techniques Analysis
- Welding Techniques and Residual Stresses
- Microstructure and Mechanical Properties of Steels
- Aluminum Alloys Composites Properties
- Metal Alloys Wear and Properties
- Aluminum Alloy Microstructure Properties
- Intermetallics and Advanced Alloy Properties
- Metal and Thin Film Mechanics
- Hydrogen embrittlement and corrosion behaviors in metals
- High Temperature Alloys and Creep
- Electronic Packaging and Soldering Technologies
- Laser and Thermal Forming Techniques
- Microstructure and mechanical properties
- Engineering Applied Research
- Fatigue and fracture mechanics
- Metal Forming Simulation Techniques
- High Entropy Alloys Studies
- Additive Manufacturing Materials and Processes
- Corrosion Behavior and Inhibition
- High-Temperature Coating Behaviors
- 3D IC and TSV technologies
- Metallurgy and Material Forming
- Advanced Surface Polishing Techniques
- Advanced ceramic materials synthesis
- Additive Manufacturing and 3D Printing Technologies
Pusan National University
2011-2024
Petronas (Malaysia)
2024
Daewoo Shipbuilding and Marine Engineering (South Korea)
2016-2022
Pohang Iron and Steel (South Korea)
2004-2018
Agency for Defense Development
2013
Convergence
2013
Korea Institute of Materials Science
2011-2012
Melting range, microstructure, mechanical properties and spreadabililty of Zn-(4∼6 mass%)Al-(1∼6 mass%)Cu alloys were investigated. Liquidus temperature was targeted between 655 675 K, solidus to 645 K. The liquidus the Zn-Al-Cu solders increased with Cu contents, but it decreased Al contents. Microstructures consisted primary ε-phase (CuZn4), η-phase (Zn matrix), α-η eutectic phase (Zn-Al eutectic) ε-η (Zn-Cu eutectic), irrespective Increasing hardness tensile strength increased, elongation...
The dissimilar Al alloys, 5052 and 5J32, were joined by friction stir welding (FSW) technique under several conditions, including material arrangement. tool rotation speeds 1000 1500 rpm, the varied within range from 100 to 400 mm/min. At a speed of all joints with on advancing side exhibited better properties than those opposite When 5J32 was placed side, defect-free welds obtained conditions. However, when retreating some defects detected below top surface side. Furthermore, fractographs...
Basic characteristics of CO2 laser welded 800 MPa class TRIP steel such as defects, microstructure, mechanical properties and formability was investigated. Bead-on-plate welding carried out under various power, speed shield gas. Porosity fraction reduced with increasing the using Ar-He mixed gas compared to Ar The maximum hardness obtained at weld metal well HAZ near metal. value same regardless nearly equal that water quenched raw In perpendicular tensile test axis, joints produced optimum...
Lately, high production rate welding processes for Al alloys, which are used as LNG FPSO cargo containment system material, have been developed to overcome the limit of installation and rework rates. In particular, plasma-metal inert gas (MIG) hybrid (PMH) can be obtain a higher deposition lower porosity, while facilitating cleaning effect by preheating post heating wire base metal. However, an asymmetric undercut black-colored deposit created on surface PMH weld in alloys. For controlling...
This study applied laser surface melting process using CW(Continuous wave) Yb:YAG and cold-work die steel SM45C investigated microstructure hardness. Laser beam speed, power interval are fixed at 70 mm/sec, 2.8 kW 800 μm respectively. Depth of Hardening layer(Melting zone) was a minimum 0.8 mm maximum 1.0 that exceeds the limit depth 0.5 applying trimming die. In all weld zone, macrostructure dendrite structure. At boundary, Mn, Al, S O segregated MnS Al oxide existed. However, this...
This study investigated the nucleation and growth mechanism of reaction layers phases hot-dipped boron steel in pure Al at 690 °C for 0–120 s. In case a dipping time 30 s, nuclei width 10–15 μm height 10 were formed on surface flow direction liquid Al. layer was as mixture θ (Fe4Al13) phase several nm to 2 μm, η (Fe2Al5) nm, columnar region, β (FeAl) region 500 thickness interface. At grain boundaries ferrite, contact with phase, κ (Fe3AlC) formed. Using calculated Fe-Al diagram, it...