Comparative studies on the pest reactions of single- and poly- crystalline MoSi sub 2

Journal Article · Wed Jul 01 04:00:00 EDT 1992 · Scripta Metallurgica et Materialia; (United States)

DOI:https://doi.org/10.1016/0956-716X(92)90312-3· OSTI ID:7088742

Chou, T C; Nieh, T G ^[1]

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1. Lockheed Research and Development Div., Palo Alto, CA (US)

Molybdenum disilicide (MoSi{sub 2}) has many attractive properties, e.g., high melting point (2020{degrees}C), relatively low density (6.28 g/cm{sup 3}), good thermal stability and thermal shock resistance, and excellent oxidation resistance, for potential high temperature applications. Specifically, it is oxidation resistant at temperatures up to about 1900{degrees}C, resulting from the formation of a self-healing, glassy silica (SiO{sub 2}) surface layer. Because of its suitability for use as a high temperature coating and as heating elements, the oxidation properties of MoSi{sub 2} have been extensively studied in the past 30 years, but mainly in the high temperature regimes. In this paper, the authors investigate the evolution and morphological characteristics of the oxidation products of both MoSi{sub 2} single crystals and cast polycrystals. Special attention is given to addressing the nucleation of pest in single crystalline material. The results from both the single- and poly-crystalline samples are correlated with an effort to resolve the origin of MoSi{sub 2} pest. Their implications to the early-stage formation (nucleation) of pest are discussed.

• OSTI ID: 7088742
• Journal Information: Scripta Metallurgica et Materialia; (United States), Journal Name: Scripta Metallurgica et Materialia; (United States) Vol. 27:1; ISSN SCRME
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360103 -- Metals & Alloys-- Mechanical Properties
360105* -- Metals & Alloys-- Corrosion & Erosion
CHEMICAL REACTIONS
COMPARATIVE EVALUATIONS
CRYSTALS
EVALUATION
MECHANICAL PROPERTIES
MOLYBDENUM COMPOUNDS
MOLYBDENUM SILICIDES
MONOCRYSTALS
MORPHOLOGY
NUCLEATION
OXIDATION
POLYCRYSTALS
REFRACTORY METAL COMPOUNDS
SILICIDES
SILICON COMPOUNDS
TEMPERATURE RANGE
TEMPERATURE RANGE 0400-1000 K
TEMPERATURE RANGE 1000-4000 K
TRANSITION ELEMENT COMPOUNDS