Si3N4 — Properties & Data | MatWorld

Si3N4

ceramic

· Si3N4

Silicon nitride (Si₃N₄) is a high-performance structural ceramic composed of silicon and nitrogen, valued for its exceptional hardness, thermal stability, and resistance to thermal shock. It is widely used in automotive engines (turbocharger rotors, glow plugs), aerospace applications, cutting tools, and bearing components where superior wear resistance and high-temperature capability are required. Engineers select Si₃N₄ over traditional metals and alumina ceramics when demanding applications require a material that maintains strength at elevated temperatures while remaining lightweight, with particular advantage in environments involving thermal cycling or abrasive wear.

turbocharger rotorsceramic cutting toolsbearing componentsengine combustion chambersthermal shock resistance applicationsaerospace valve seats

Compliance & Regulations

?Conflict Free?RoHS?REACH?TSCA?Prop 65

Units:

Property	Value	Unit	Conditions	Source
Bulk Modulus(K)3 entries	34,003.8	ksi	—
↳	34,003.8	ksi	—
↳	24,038.6	ksi	—
Elastic Compliance Tensor(Sij)	Matrix (redacted)	1/GPa	—
Elastic Anisotropy(AU)	0.3757	-	—
Elastic Stiffness Tensor(Cij)	Matrix (redacted)	ksi	—
Poisson's Ratio(ν)2 entries	0.2806	-	—
↳	-0.5800	-	—
Shear Modulus(G)3 entries	17,474.7	ksi	—
↳	17,474.7	ksi	—
↳	7,262	ksi	—

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, or test environment.

Verified Unverified Low confidence (<80%) Link to source

Property	Value	Unit	Conditions	Source
Thermal Conductivity(k)	17.33	BTU/(hr·ft·°F)	—

Verified Unverified Low confidence (<80%) Link to source

Property	Value	Unit	Conditions	Source
Density(ρ)	0.1116	lb/in³	—

Verified Unverified Low confidence (<80%) Link to source

Property	Value	Unit	Conditions	Source
Band Gap(Eg)2 entries	5.100	eV	—
↳	1.431	eV	—
Dielectric Constant (Relative Permittivity)(εr)2 entries	8.160	-	—
↳	8.191	-	—
Electronic Dielectric Tensor(ε∞)	Matrix (redacted)	-	—
Total Dielectric Tensor(ε)	Matrix (redacted)	-	—
Magnetic Moment(μB)	0.000	µB	—
Piezoelectric Modulus(eij)	0.1411	C/m²	—
Seebeck Coefficient(S)	-252.9	µV/K	—

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, or test environment.

Verified Unverified Low confidence (<80%) Link to source

Property	Value	Unit	Conditions	Source
Energy Above Hull(ΔEhull)	0.7422	eV/atom	—
Formation Energy(ΔHf)2 entries	-1.103	eV/atom	—
↳	-0.4503	eV/atom	—

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, or test environment.

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.