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Vol.41, No.2, 121 ~ 131, 2002
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| Title |
| Surface Treatment : Microstructure and Wear Properties of (TiC, TiB)/Ti-6Al-4V Surface-Alloyed Materials Fabricated by High-Energy Electron Beam Irradiation |
| 이창섭 Chang Sup Lee , 오준철 Jun Cheol Oh , 이성학 Sung Hak Lee |
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| Abstract |
| The present study is concerned with the microstructural analysis and the evaluation of hardness and wear properties of (TiC,TiB)/Ti-6Al-4V surface-alloyed materials fabricated by high-energy electron beam irradiation. The mixtures of Ti+C, TiC+TiB_2, and Ti+B_4C powders and CaF_2 flux were deposited on a Ti-6Al-4V substrate, and then electron beam was irradiated on these mixtures using an electron beam accelerator. The surface-alloyed layers of 0.9∼1.6mm in thickness were formed without defects, and contained a large amount (30∼44vol.%) of precipitates such as TiC and TiB in the martensitic matrix. This microstructural modification including the formation of hard precipitates and hardened matrix in the surface-alloyed layers resulted in the improvement hardness and wear resistance. Particularly in the surface-alloyed material fabricated with Ti+B_4C powders, the wear resistance was greatly enhanced by nine times higher than that of the Ti alloy substrate because a 44 vol.% of TiB and TiC was precipitated homogeneously in the martensitic matrix. These findings suggested that the surface-alloying using high-energy electron beam irradiation was useful for the development of titanium-base surface-alloyed materials with increased surface hardness and improved wear properties. |
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| Key Words |
| Surface alloying, Electron beam irradiation, Ti-6A1-4V, TiC, TiB, Flux, Wear resistance, Hardness |
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