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Vol.56, No.3, 197 ~ 205, 2018
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| Title |
| Microstructure of Rhenium Coatings Deposited by CVD on Graphite and Mo Substrates |
| 이선규 Sun Kyu Lee , 남동윤 Dong Yun Nam , 배남호 Nam Ho Bae , 임성택 Sung Taek Lim , 오용준 Yong-jun Oh |
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| Abstract |
| Rhenium coatings were fabricated on a graphite substrate at 1100 and 1250 ℃ and a molybdenum substrate at 1150 and 1250 ℃ by chemical vapor deposition (CVD) using ReCl5 precursor, and the effects of deposition temperatures and substrates on microstructure and crystal orientation were investigated. The rhenium coating on graphite infiltrated the pores about hundred micrometers into the graphite, resulting in a large contact area between the coating and the graphite. However, the rhenium coating on molybdenum showed inferior adhesion, introducing voids and cracks in the Mo metal due to additional reactions between the precursor and Mo. As deposition temperature increased, rhenium grains on the graphite increasingly developed a preferred (0002) orientation normal to the coating, while on molybdenum they tended to develop other orientations, such as pyramidal and prism planes. These behaviors were discussed in relation to interfacial microstructure.
(Received October 18, 2017; Accepted January 5, 2018) |
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| Key Words |
| coating, vapor deposition, rhenium, microstructure, texture |
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