【開催報告】2026.09.29 -第199回構材ゼミ- Dr. Praveen Kumar (Department of Materials Engineering Indian Institute of Science, Bangalore, India)
講演後の集合写真
Prof. Praveen Kumar (右から6番目)
- 日時
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2026年9月29日（火曜日）14：30-15:30
- 場所
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NIMS千現地区 先進構造材料研究棟5階カンファレンスルーム
- 講演題目
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Manipulating Structural Integrity of Pre-Cracked Thin Metallic Sheets through Electric Current Pulsing
- 講演者
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Dr. Praveen Kumar
Department of Materials Engineering Indian Institute of Science, Bangalore, India
Abstract:
Recent studies have shown that the passage of an electric current pulse may both propagate [1,2] and close a crack and heal a metallic material [3]. Specifically, experiments on thin Al foils containing edge cracks have proved that the self-induced electromagnetic forces, spontaneously generated upon passage of an electric current across a crack in a sample, alone could cause crack propagation without melting of the crack tip [1]. The critical current density required for crack propagation reduces in the presence of an external magnetic field [4] as well as mechanical load [5]. On the other hand, if an electric current pulse of large pulse width is passed through an electrically and thermally resistive material, such as stainless steel, containing a short crack, the crack may completely close, and the material can heal through the solid-state diffusion bonding process [3]. Here, we discuss the reasons behind crack propagation upon application of electric current and then explore the mechanics as well as microstructural attributes responsible for a transition from flaw propagation to flaw healing upon passage of an electric current pulse. Furthermore, the recovery of the mechanical properties of the material upon electric current-induced healing will also be discussed.
References:
1. D. Sharma, B. Subba Reddy and P. Kumar, “Fracture of pre-cracked thin metallic conductors due to electric current induced electromagnetic force”, Int. J. Fracture 212 (2018) 183.
2. D. Sharma and P. Kumar, “Failure of thin metallic conductors under electric current loading: Transition from sharp crack to blow-hole”, Eng. Fracture Mech. 208 (2019) 221
3. S Telpande, C Kumar, D Sharma, and Praveen Kumar, “Electric current-induced solid-state crack healing and life extension”, Acta Mater 283 (2025) 120573.
4. S Telpande, S Jain, P Kumar, “Effect of external magnetic field on electric current-induced fracture of notched thin metallic conductors: Part 1–Low magnetic fields”, Theoretical and Applied Fracture Mechanics 130 (2024) 104301.
5. D. Sharma, B. Subba Reddy and P. Kumar, “Fracture of pre-cracked metallic conductors under combined electric current and mechanical loading”, Int. J. Fracture 212 (2018) 167.
Acknowledgement:
＊ Swanand Telpande, Deepak Sharma, Chandan Kumar and Subham Jain
＊ Department of Science and Technology (DST), India and Council of Scientific and Industrial Research (CSIR), India
Brief Bio
Praveen Kumar received his Bachelor of Technology degree in Mechanical Engineering from the Indian Institute of Technology, Kanpur (India) in 2003. Subsequently, he received M.S. and Ph.D. degrees in Mechanical Engineering, with emphasis on Materials, from the University of Southern California, Los Angeles (USA) in 2005 and 2007, respectively. He joined the Department of Materials Engineering at the Indian Institute of Science, Bangalore (India) in May 2011 as an assistant professor, and he has been working therein as a professor since May 2023. His main research interests are the mechanical behavior of materials, with particular emphasis on studying the effects of electric current, temperature and sample length scale and constructive usage of electromigration, both in solid and liquid metals. His works involve structure-property relationships to gain fundamental insights into the structural integrity of structures, as well as the development of high-throughput mechanical test methodologies. He has received scientific awards, including Abdul Kalam Technology Innovation National Fellowship from the Indian National Academy of Engineering (2022-2025), Young Scientist Award from the Indian National Science Academy (2016), etc.