Ki-Hang Shin
Current Organizations / Institutes
The organizations/institutes from the scholar's latest article
Research Subjects
Ki-Hang Shin has a total of 4 co-authors. Here are the top co-authors by number of shared publications:
- Jimin Yun
Department of Marine Design Convergence Engineering, Pukyong National University, 45 Yongso-ro, Nam-gu, Busan 48513, Republic of Korea
2 shared publications - Ki-Woo Nam
Pukyong National University
2 shared publications - Kwonhoo Kim
Department of Marine Design Convergence Engineering, Pukyong National University, 45 Yongso-ro, Nam-gu, Busan 48513, Republic of Korea
2 shared publications - Ho Seok Nam
Busan Development Institue, Busan 47210, Republic of Korea
1 shared publication
Latest Publications
- Open Access
The Effect of Shot Peening on Corrosion Resistance of 18Ni300 Maraging Steel Manufactured by LPBF
This study investigated the correlation between mechanical strengthening and electrochemical corrosion behavior in 18Ni300 maraging steel fabricated via laser powder bed fusion (LPBF). To evaluate the impact of post-processing, specimens were analyzed under four conditions: solution treated (S), solution peened (SP), solution aged (SA), and solution aged peened (SAP). The aging treatment (490 °C for 6 h) effectively enhanced the corrosion resistance by homogenizing the martensitic matrix and promoting the formation of a stable passive film, resulting in the lowest corrosion current density ( of 1.716 × 10−6 A/cm2). In contrast, the application of shot peening after aging (SAP) significantly degraded the corrosion resistance, characterized by the most negative corrosion potential ( of −0.374 V and a 2.4 times increase in compared to the SA condition. Quantitative analysis revealed that the 1250 MPa of compressive residual stress induced by peening increased the thermodynamic instability of the surface through extreme lattice distortion, thereby lowering the activation energy for anodic dissolution. Furthermore, the increased surface roughness (60.68 µm) expanded the effective electrochemical reaction area, acting as a kinetic accelerator for corrosion. The results demonstrate that while the SA process provides an optimal balance between microstructural stability and corrosion resistance, additional shot peening (SAP) imposes a significant corrosion penalty despite its mechanical benefits. This study concludes that for 18Ni300 maraging steel, the trade-off between mechanical reinforcement and electrochemical stability must be carefully managed, emphasizing the need for surface stabilization when high-intensity peening is applied in corrosive environments.Open AccessThe Effect of Shot Peening on Corrosion Resistance of 18Ni300 Maraging Steel Manufactured by LPBF
This study investigated the correlation between mechanical strengthening and electrochemical corrosion behavior in 18Ni300 maraging steel fabricated via laser powder bed fusion (LPBF). To evaluate the impact of post-processing, specimens were analyzed under four conditions: solution treated (S), solution peened (SP), solution aged (SA), and solution aged peened (SAP). The aging treatment (490 °C for 6 h) effectively enhanced the corrosion resistance by homogenizing the martensitic matrix and promoting the formation of a stable passive film, resulting in the lowest corrosion current density ( of 1.716 × 10−6 A/cm2). In contrast, the application of shot peening after aging (SAP) significantly degraded the corrosion resistance, characterized by the most negative corrosion potential ( of −0.374 V and a 2.4 times increase in compared to the SA condition. Quantitative analysis revealed that the 1250 MPa of compressive residual stress induced by peening increased the thermodynamic instability of the surface through extreme lattice distortion, thereby lowering the activation energy for anodic dissolution. Furthermore, the increased surface roughness (60.68 µm) expanded the effective electrochemical reaction area, acting as a kinetic accelerator for corrosion. The results demonstrate that while the SA process provides an optimal balance between microstructural stability and corrosion resistance, additional shot peening (SAP) imposes a significant corrosion penalty despite its mechanical benefits. This study concludes that for 18Ni300 maraging steel, the trade-off between mechanical reinforcement and electrochemical stability must be carefully managed, emphasizing the need for surface stabilization when high-intensity peening is applied in corrosive environments. - Open Access
Study on Decarburization and Mechanical Properties of Ultra-Low Carbon Steel by Enlarged Vacuum Chamber Volume
The increasing demand for ultra-low carbon steel (Interstitial free steel of Ti-Nb composite stabilized type) has underscored the importance of the RH degassing process, which is critical to achieving stringent quality standards and high productivity. This study aimed to boost decarburization efficiency by expanding the lower volume of the RH degasser and adjusting the circulation gas flow rates (190 Nm3/h, 230 Nm3/h, 250 Nm3/h). The effects of these variations on decarburization time, carbon content, and mechanical properties were systematically evaluated. The Enlarged RH degasser (ERH) achieved a higher decarburization rate than the conventional RH degasser (CRH) at the same gas flow rate of 190 Nm3/h, identifying 230 Nm3/h as the optimal rate for ERH. The experimental decarburization times to reach a carbon content of 0.003 wt% in ultra-low carbon steel were 12.4 min for CRH and 10.8 min for ERH, thus reducing the time by 1.6 min. Conversely, the calculated decarburization times were 13.11 min for CRH and 10.75 min for ERH, with ERH showing a reduction of 2.36 min. Consequently, calculated times were 0.76 min longer than experimental times. No significant differences in inclusions were observed between the CRH and ERH at circulation times of 3, 4, and 5 min; however, the mechanical properties of the ERH showed improvements at 4 and 5 min. Therefore, from an economic perspective, 4 min was established as the optimum time. Ultimately, enhancing the lower volume of the RH degasser has increased productivity and decreased production costs.
Open AccessStudy on Decarburization and Mechanical Properties of Ultra-Low Carbon Steel by Enlarged Vacuum Chamber Volume
The increasing demand for ultra-low carbon steel (Interstitial free steel of Ti-Nb composite stabilized type) has underscored the importance of the RH degassing process, which is critical to achieving stringent quality standards and high productivity. This study aimed to boost decarburization efficiency by expanding the lower volume of the RH degasser and adjusting the circulation gas flow rates (190 Nm3/h, 230 Nm3/h, 250 Nm3/h). The effects of these variations on decarburization time, carbon content, and mechanical properties were systematically evaluated. The Enlarged RH degasser (ERH) achieved a higher decarburization rate than the conventional RH degasser (CRH) at the same gas flow rate of 190 Nm3/h, identifying 230 Nm3/h as the optimal rate for ERH. The experimental decarburization times to reach a carbon content of 0.003 wt% in ultra-low carbon steel were 12.4 min for CRH and 10.8 min for ERH, thus reducing the time by 1.6 min. Conversely, the calculated decarburization times were 13.11 min for CRH and 10.75 min for ERH, with ERH showing a reduction of 2.36 min. Consequently, calculated times were 0.76 min longer than experimental times. No significant differences in inclusions were observed between the CRH and ERH at circulation times of 3, 4, and 5 min; however, the mechanical properties of the ERH showed improvements at 4 and 5 min. Therefore, from an economic perspective, 4 min was established as the optimum time. Ultimately, enhancing the lower volume of the RH degasser has increased productivity and decreased production costs.