HfSi2

ceramic
· HfSi2

Hafnium disilicide (HfSi2) is an intermetallic ceramic compound belonging to the refractory silicide family, characterized by exceptionally high melting points and oxidation resistance at elevated temperatures. It is primarily used in ultra-high-temperature structural applications and thermal protection systems, particularly in aerospace propulsion and hypersonic vehicle design where materials must withstand extreme thermal cycling and oxidative environments. HfSi2 offers advantages over competing refractory ceramics and metal alloys due to its combination of rigidity at temperature, relatively low density compared to other refractory silicides, and chemical stability in oxygen-rich atmospheres, making it valuable for applications where conventional nickel-based superalloys or alumina ceramics reach their performance limits.

hypersonic vehicle structuresrocket engine nozzlesthermal protection systemshigh-temperature coatingsaerospace propulsion componentsrefractory composite reinforcement

Compliance & Regulations

?Conflict Free?RoHS?REACH?TSCA?Prop 65
PropertyValueUnitConditionsSource
Bulk Modulus(K)3 entries
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Elastic Compliance Tensor(Sij)
Matrix (redacted)
1/GPa
Elastic Anisotropy(AU)
-
Elastic Stiffness Tensor(Cij)
Matrix (redacted)
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Poisson's Ratio(ν)2 entries
-
-
Shear Modulus(G)3 entries
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N entriesMultiple entries per property — large groups are collapsed; click a summary row to expand. Use filters above to narrow by form / heat treatment / basis.
Verified Unverified Low confidence (<80%) Link to source
PropertyValueUnitConditionsSource
Density(ρ)
lb/in³
Verified Unverified Low confidence (<80%) Link to source
PropertyValueUnitConditionsSource
Band Gap(Eg)
eV
Magnetic Moment(μB)
µB
Seebeck Coefficient(S)
µV/K
Verified Unverified Low confidence (<80%) Link to source
PropertyValueUnitConditionsSource
Energy Above Hull(ΔEhull)
eV/atom
Formation Energy(ΔHf)
eV/atom
Verified Unverified Low confidence (<80%) Link to source

Regulatory Screening

Environmental

RoHS, REACH, and Prop 65 statuses are validated against official substance lists (ECHA SVHC Candidate List, OEHHA Prop 65, RoHS Annex II). Other regulations are estimated from composition and material classification. All screening is a starting point for due diligence — always verify with your supplier before making compliance decisions.