Impression creep behavior of SiC particle-MoSi{sub 2} composites

Journal Article · Sat Jun 01 04:00:00 EDT 1996 · Journal of Materials Research

DOI:https://doi.org/10.1557/JMR.1996.0191· OSTI ID:285871

Butt, D P; Korzekwa, D A; Maloy, S A; Kung, H; Petrovic, J J ^[1]

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1. Materials Science and Technology Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States)

Using a cylindrical indenter (or punch), the impression creep behavior of MoSi{sub 2}-SiC composites containing 0{endash}40{percent} SiC by volume, was characterized at 1000{endash}1200{degree}C, 258{endash}362 MPa punch pressure. Through finite element modeling, an equation that depends on the material stress exponent was derived that converts the stress distribution beneath the punch to an effective compressive stress. Using this relationship, direct comparisons were made between impression and compressive creep studies. Under certain conditions, compressive creep and impression creep measurements yield comparable results after correcting for effective stresses and strain rates beneath the punch. However, rate-controlling mechanisms may be quite different under the two stressing conditions, in which case impression creep data should not be used to predict compressive creep behavior. The addition of SiC affects the impression creep behavior of MoSi{sub 2} in a complex manner by pinning grain boundaries during pressing, thus leading to smaller MoSi{sub 2} grains and by obstructing or altering both dislocation motion and grain boundary sliding. {copyright} {ital 1996 Materials Research Society.}

• OSTI ID: 285871
• Journal Information: Journal of Materials Research, Journal Name: Journal of Materials Research Journal Issue: 6 Vol. 11; ISSN JMREEE; ISSN 0884-2914
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
ACTIVATION ENERGY
COMPOSITE MATERIALS
COMPUTERIZED SIMULATION
CREEP
DISLOCATION PINNING
FINITE ELEMENT METHOD
GRAIN BOUNDARIES
MOLYBDENUM SILICIDES
SILICON CARBIDES
TEMPERATURE DEPENDENCE
TEMPERATURE RANGE 1000-4000 K