Yoon, JK Kim, GH Byun, JY Lee, JK Kim, JS 2024-01-21T09:14:28Z 2024-01-21T09:14:28Z 2021-09-01 2003-02-03 0257-8972 https://pubs.kist.re.kr/handle/201004/138826 The formation of crack-free MOSi2/alpha-Si3N4 composite coating on a Mo substrate by ammonia nitridation followed by chemical vapor deposition (CVD) of Si on the Mo5Si3 layer at 1100 degreesC which was already formed on a Mo substrate was investigated using optical microscopy, field-emission scanning electron microscopy (SEM), cross-sectional transmission electron microscopy (XTEM) and X-ray diffraction (XRD). This study demonstrated that the crack-free MoSi2/alpha-Si3N4 composite coating with some pores could be produced on a Mo substrate. Two composite layers (gamma-Mo2N/alpha-Si3N4 and Mo3Si/alpha-Si3N4) with different microstructure were formed by ammonia nitridation of Mo5Si3 layer, and the subsequent CVD of Si resulted in the formation of three composite layers (MoSi2/oblate-spheroidal type alpha-Si3N4, gamma-Mo2N/rod type alpha-Si3N4 and MO3Si/alpha-Si3N4). The volume percentage of alpha-Si3N4 phase in the MoSi2/alpha-Si3N4 composite coating ranged from 30 to 33%, suggesting that the thermal expansion coefficient of composite coating was close to that of Mo substrate. (C) 2002 Elsevier Science B.V. All rights reserved. English ELSEVIER SCIENCE SA THERMAL-EXPANSION MOLYBDENUM TEMPERATURE BEHAVIOR ALLOYS MOSI2 Formation of crack-free MoSi2/alpha-Si3N4 composite coating on Mo substrate by ammonia nitridation of Mo5Si3 layer followed by chemical vapor deposition of Si Article 10.1016/S0257-8972(02)00722-3 1 SURFACE & COATINGS TECHNOLOGY, v.165, no.1, pp.81 - 89 SURFACE & COATINGS TECHNOLOGY 165 1 81 89 scie scopus 000180293900010 2-s2.0-0346034944 Materials Science, Coatings & Films Physics, Applied Materials Science Physics Article THERMAL-EXPANSION MOLYBDENUM TEMPERATURE BEHAVIOR ALLOYS MOSI2 ammonia nitridation and CVD of Si crack-free MoSi2/alpha-Si3N4 composite coating molybdenum