Microstructure Change of Molybdenum Disilicide Heating Unit in Nitrogen Atmosphere at 1700°C
Transformation of the microstructure of molybdenum disilicide heating unit in nitrogen atmosphere at 1700°C was investigated by XRD, SEM and EDS. The results showed that MoSi2 was transformed to polyhedral Si3N4 crystals groups distributed across in the matrix with irregular geometry Mo5Si3 and Mo3Si crystals, and the Si3N4 crystal groups were dense areas, while the Mo5Si3 and Mo3Si groups were loose areas after being heated in nitrogen atmosphere at 1700°C for 3h. The thickness of conversion zone of MoSi2 matrix was about 30μm and the loose Mo5Si3 and Mo3Si areas can damage the dense structure of MoSi2 matrix.
Wei Pan and Jianghong Gong
B. L. Liu et al., "Microstructure Change of Molybdenum Disilicide Heating Unit in Nitrogen Atmosphere at 1700°C", Key Engineering Materials, Vols. 368-372, pp. 955-957, 2008