교수님께서 2023년도 숭실대학교 교육업적 SFP(Soongsil Fellowship Professor)를 수상하셨습니다. 진심으로 축하드리고 연구 업적 SFP도 받는 날을 고대하며 다같이 더욱 노력하겠습니다!

Author: H.Kim†, J.Kwak†, J.Lee, I.Kim, J.Kim*Title: Development of Innovative MAX Phase Bond Coats for Thermal Barrier Coatings using Multi-scale Simulations Journal: Journal of Materials Research and TechnologyYear: 2025Impact factor: 6.2Abstract:Thermal barrier coatings (TBCs) can face significant thermal and residual stress, particularly at high temperatures. To address this challenge, bond coats (BCs) are needed that can effectively mitigate these stresses. This work designs innovative MAX phase (Cr2AlC, Mo2AlC, and W2AlC) BCs with the aim of enhancing thermal shock and crack resistance using multi-scale simulations. The results show Mo2AlC to be particularly suitable as a BC due to its thermal expansion compatibility with both the thermally grown oxide (TGO, Al2O3) and the substrate, outperforming conventional metallic BCs. The small difference in CTE between the MAX phases and TGO or top coat can effectively relieve thermal stress. Also, the BC Mo2AlC with substrate IN617 has the highest flexural strength at high temperature, which has the highest crack resistance. This paper reports on the computational discovery of novel MAX phases, paving the way for the next generation of durable TBCs.

Author: J.Choi†, H.Kim, I.Bae, H.Son, J.Kim*Title: Materials design workflow for extreme environments via computational method: Transition metal-doped (Hf0.5Ta0.5)CJournal: Journal of Materials Research and TechnologyYear: 2025Impact factor: 6.2Abstract:The development of materials such as superalloys, ceramics, and composites for use in extreme environments poses major challenges owing to difficulties associated with those environments, including thermal shock and oxidation. Much research is focusing on optimizing compositions to withstand these conditions. In the present work, a computational workflow for designing compositions was developed. The method was applied to (Hf0.5Ta0.5)C, a representative material suited to extreme environments, but which suffers problems under oxidation conditions due to the low melting point of Ta2O5. Twenty-two potential transition-metal doping elements were screened, and Ti, Zr, Nb, and W were selected because of the excellent mechanical properties of the resulting solid solutions. Ab initio molecular dynamics simulations of oxidation showed that Ti and Zr doping could improve resistance to oxidation by promoting the oxidation of Hf and slowing that of Ta in the (Hf0.5Ta0.5)C. Additionally, Ta, Zr, and Nb doping increased the relative mobility of Hf, which supported sustained Hf oxide growth, as confirmed by nudged elastic band calculations. The results indicate that the appropriate selection of doping elements can enhance the performance with (Hf0.5Ta0.5)C, demonstrating the utility of the proposed composition design workflow.

Author: H.Lee†, J.Kim†, S.Kyung, H.Kim, Y.Jung, J.Park, J.Kim*Title: Ab initio Calculations of 312 MAX Phases as Matrix for Carbon Fiber Reinforced Ceramics Journal: Textile Science and EngineeringYear: 2025Abstract:Carbon fiber reinforced ceramics (CFRCs) are well-suited for aerospace components due to their high-temperature stability and oxidation resistance. The SiC-based matrix offers excellent fracture toughness and thermal shock resistance but is prone to defects such as cracking and delamination due to its brittleness. To address these issues, ongoing research focuses on incorporating MAX phase ceramics into composites. In this study, tailoring the M-site composition in MAX phases, such as M3SiC2 structures, expands the mechanical and thermal properties using ab initio calculations. This study identified that Ta-based M3SiC2 MAX phases exhibit high bulk modulus, making them resistant to pressure changes, while Ti and Hf-based phases demonstrate high shear and Young’s modulus, contributing to superior crack resistance and thermal durability. Additionally, Ti, Zr, Hf, and Ta-based compositions were found to have thermal expansion properties like SiCf effectively mitigating thermal stress and fatigue under rapid temperature fluctuations. Ab initio calculations identified Ti, Zr, Hf, and Ta-based M3SiC2 MAX phases as the most promising matrix materials for CFRCs in aerospace and high-temperature applications.

Author: S.Kyung†, J.Choi†, J.Kwak, J.Kim*Title: Computational design of transition metal nitrides (Ti1−xMx)N (M = Ti, V, Cr, Zr, Nb, Mo, Hf, Ta, and W) for coatingsJournal: International Journal of Applied Ceramic TechnologyYear: 2025Abstract:The development of coatings with high-performance applications such as cutting tools and aerospace fields is essential because high temperatures during machining and processing shorten the lifespan of tools. We investigated the structural information and mechanical properties of (Ti1-xMx)N (0.0625 ≤ x ≤ 0.125) (M = V, Cr, Zr, Nb, Mo, Hf, Ta, and W) using ab initio calculation. We provide specific guidance for enhancing the performance of TiN-based coatings via ab initio calculation. Through this study, we suggest that (Ti0.875W0.125)N, which exhibits the highest hardness, is a suitable candidate for cutting tools and aerospace coating materials.