High temperature deformation behaviour of MoSi2 and WSi2 single crystals

Kimura, Kazuhiro; Nakamura, Morihiko; Hirano, Tôru

doi:10.1007/bf00638047

Cited by 53 publications

(6 citation statements)

References 18 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Stacking faults on (001) in as-grown and plastically deformed MoSi 2 have been observed by many researchers. [22,23,29–31]. We have also observed similar stacking faults on (001) formed during high-temperature compression tests of [001]-oriented single crystals of WSi 2 with the C11 b crystal structure and proposed a possible formation mechanism, in which the (001) stacking fault is formed by the climb motion of 1/6<331> partial dislocations that originate from a <100> perfect dislocation.…”

Section: Resultssupporting

confidence: 58%

Plastic deformation of directionally solidified ingots of binary and some ternary MoSi₂/Mo₅Si₃ eutectic composites

Matsunoshita

Sasaki

Fujiwara

et al. 2016

Science and Technology of Advanced Materials

View full text Add to dashboard Cite

The high-temperature mechanical properties of directionally solidified (DS) ingots of binary and some ternary MoSi2/Mo5Si3 eutectic composites with a script lamellar structure have been investigated as a function of loading axis orientation and growth rate in a temperature range from 900 to 1500°C. These DS ingots are plastically deformed above 1000 and 1100 °C when the compression axis orientations are parallel to [10]MoSi2 (nearly parallel to the growth direction) and [001]MoSi2, respectively. [10]MoSi2-oriented DS eutectic composites are strengthened so much by forming a script lamellar microstructure and they exhibit yield stress values several times higher than those of MoSi2 single crystals of the corresponding orientation. The yield stress values increase with the decrease in the average thickness of MoSi2 phase in the script lamellar structure, indicating that microstructure refinement is effective in obtaining better high-temperature strength of these DS eutectic composites. Among the four ternary alloying elements tested (V, Nb, Ta and W), Ta is found to be the most effective in obtaining higher yield strength at 1400 °C.

show abstract

Section: Resultssupporting

confidence: 58%

Plastic deformation of directionally solidified ingots of binary and some ternary MoSi₂/Mo₅Si₃ eutectic composites

Matsunoshita

Sasaki

Fujiwara

et al. 2016

Science and Technology of Advanced Materials

View full text Add to dashboard Cite

show abstract

“…In spite of the fact that crystal structure, lattice parameters, melting point, coefficient of thermal expansion, elastic constants and electronic structure of WSi 2 are very similar to those of MoSi 2 , the plastic deformation behaviour differs significantly. The studies on deformation behaviour of single crystals of WSi 2 by Kimura and co-workers 41,42 have indicated that single crystals of WSi 2 oriented near the n001m and n100m directions exhibit plastic flow at 1300uC and above, with slip occurring on the {01 ¯3}n331m and {11 ¯0}n331m systems, respectively (Table 15). In addition, stacking faults have been observed in the {110} planes.…”

Section: Deformation Behaviour Of Other Silicidesmentioning

confidence: 99%

Mechanical behaviour and oxidation resistance of structural silicides

Mitra¹

2006

International Materials Reviews

256

View full text Add to dashboard Cite

The need for high performance materials in aerospace, automotive and industrial components operating at temperatures in the range of 1100-1500uC has led to a surge in the research and development of the refractory metal silicide based intermetallics, multiphase alloys and composites. The silicides of Mo, W, Ti, Nb and Cr are attractive for high melting points, strength retention and ductile behaviour, combined with reasonable to excellent oxidation resistance at elevated temperatures. The major limitation to the widespread use of structural silicides is their inherent brittleness and poor fracture toughness at room temperature, which may be improved further by suitable alloying or tailoring composite microstructures or use of innovative processing routes. The high temperature deformation behaviour of the structural silicides is complex, and depends on the composition and alloy content, crystal structure, character of bonding and orientation, microstructural constitution (nature of phases present and volume fraction), and grain size. Over the past decade, the basic character and role of dislocations involved in the deformation of single or polycrystalline samples at different temperatures and strain rates, including creep conditions, have been investigated in order to understand the operating mechanisms and decide on the strategies to further improve the mechanical properties. Oxidation behaviour in different structural silicides has been studied with emphasis on the constitution of the oxide scale and the kinetics of oxidation under different temperature regimes, which also involve pest disintegration at intermediate temperatures. The present study is a review with a comparative assessment of the known mechanisms of deformation, fracture and oxidation along with strategies to improve the properties to the targeted levels and some of the emerging applications of structural silicides.

show abstract

“…They observed dislocation motion on {0 1 1}<1 0 0> and {0 1 3}<3 3 1> slip systems at room temperature, whereas deformation on the other slip systems only took place at temperatures higher than 300 • C [1]. In general, slip on {0 1 1}<1 0 0> followed Schmid's law, but in contrast, studies on {0 1 3}<3 3 1> show the highest CRSS in the exact [0 0 1] orientation and a CRRS value close to the other known slip systems in orientations away from [0 0 1] [1,2,26,27,28,29]. That is, Schmid's law is not valid for slip on {0 1 3}<3 3 1> slip systems, because the CRSS strongly depends on crystal orientation.…”

Section: Background: Structure and Deformation Of Mosimentioning

confidence: 88%

“…They attributed the high anisotropy to the activation of two different slip systems: only the hard (high CRSS) {0 1 3}<3 3 1> slip system was activated in orientations close to [0 0 1], whereas in orientations away from [0 0 1], deformation on the soft (low CRSS) {1 1 0}<3 3 1> slip system could also be detected. The study published by Kimura et al [27] is in good agreement with the results of Umakoshi et al [26]. The works of Mitchel and Maloy [28] and Maloy et al [29] are controversial concerning the possible slip systems in MoSi 2 , identifying the operating slip systems as {0 1 3}<3 3 1> below 1300 • C and {0 1 1}<1 1 1> above 1300 • C in the [0 0 1] orientation, and {1 1 0}<1 1 1> and {0 1 1}<1 0 0> in all other deformation directions.…”

Section: Background: Structure and Deformation Of Mosimentioning

confidence: 99%

Low temperature deformation of MoSi2 and the effect of Ta, Nb and Al as alloying elements

et al. 2019

View full text Add to dashboard Cite

Molybdenum disilicide (MoSi 2 ) is a very promising material for high temperature structural applications due to its high melting point (2030 • C), low density, high thermal conductivity and good oxidation resistance. However, MoSi 2 has limited ductility below 900 • C due to its anisotropic plastic deformation behaviour and high critical resolved shear stresses on particular slip systems.Nanoindentation of MoSi 2 microalloyed with aluminium, niobium or tantalum showed that all alloying elements cause a decrease in hardness. Analysis of surface slip lines indicated the activation of the additional {1 1 0}<1 1 1> slip system in microalloyed MoSi 2 , which is not active below 300 • C in pure MoSi 2 . This was confirmed by TEM dislocation analysis of the indentation plastic zone. Further micropillar compression experiments comparing pure MoSi 2 and the Ta-alloyed sample enabled the determination of the critical resolved shear stresses of individual slip systems even in the most brittle [0 0 1] crystal direction.

show abstract

High temperature deformation behaviour of MoSi2 and WSi2 single crystals

Cited by 53 publications

References 18 publications

Plastic deformation of directionally solidified ingots of binary and some ternary MoSi₂/Mo₅Si₃ eutectic composites

Plastic deformation of directionally solidified ingots of binary and some ternary MoSi₂/Mo₅Si₃ eutectic composites

Mechanical behaviour and oxidation resistance of structural silicides

Low temperature deformation of MoSi2 and the effect of Ta, Nb and Al as alloying elements

Contact Info

Product

Resources

About

High temperature deformation behaviour of MoSi2 and WSi2 single crystals

Cited by 53 publications

References 18 publications

Plastic deformation of directionally solidified ingots of binary and some ternary MoSi2/Mo5Si3 eutectic composites

Plastic deformation of directionally solidified ingots of binary and some ternary MoSi2/Mo5Si3 eutectic composites

Mechanical behaviour and oxidation resistance of structural silicides

Low temperature deformation of MoSi2 and the effect of Ta, Nb and Al as alloying elements

Contact Info

Product

Resources

About

Plastic deformation of directionally solidified ingots of binary and some ternary MoSi₂/Mo₅Si₃ eutectic composites

Plastic deformation of directionally solidified ingots of binary and some ternary MoSi₂/Mo₅Si₃ eutectic composites