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1510 |
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Impact behavior characterization of engineering metals
in kinetic spraying
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Gyuyeol Bae* / Kinetic Spray Coating Laboratory (NRL), Division of Materials Science & Engineering, Hanyang University, Korea S. Kumar / Kinetic Spray Coating Laboratory (NRL), Division of Materials Science & Engineering, Hanyang University, 17 Haengdang-dong, Seongdong-ku, Korea Sanghoon Yoon/ Kinetic Spray Coating Laboratory (NRL), Division of Materials Science & Engineering, Hanyang University, 17 Haengdang-dong, Seongdong-ku, Korea Kicheol Kang/ Kinetic Spray Coating Laboratory (NRL), Division of Materials Science & Engineering, Hanyang University, 17 Haengdang-dong, Seongdong-ku, Korea Changhee Lee/ Kinetic Spray Coating Laboratory (NRL), Division of Materials Science & Engineering, Hanyang University, 17 Haengdang-dong, Seongdong-ku, Korea |
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In this study, various engineering metals widely used as feedstock and substrates in kinetic spraying process were classified into four cases, i.e., soft/soft, hard/hard, hard/soft and soft/hard (particle/substrate), according to their physical and mechanical properties respectively. Based fon micro thermo-mechanical finite element modeling, impacting interface elements of four cases were numerically analyzed and impact behavior was characterized. For soft/soft and hard/hard cases, the maximum temperature at the side of substrate, which approached melting point, was higher than that of particle side when the shear instabilities occur. Meanwhile, for soft/hard, hard/soft cases, the specific aspect of shear instability, which has very high heat-up rate, was always observed at the relatively soft impact counterpart, and a thin molten layer was expected as well. Thus, the successful bonding of the above mentioned four cases can be predicted as a result of the synergistic effect of localized shear instability with interfacial melting. Furthermore, based on these phenomenological characteristics, critical velocities for various particle/substrate combinations were numerically estimated. |