Mg2SiO4
Mg2SiO4 (forsterite) is a magnesium silicate ceramic built on the olivine mineral base and supplied to IEC 60672 classes C-250 and C-240.
Reference datasheet — Mg2SiO4 is not in the instant-quote catalog. Upload your part and an engineer will quote it in this grade or suggest the closest stocked equivalent.
Values for the C-250 condition
Mg2SiO4 tempers and conditions
Mg2SiO4 is supplied in 2 conditions, soft to hard. C-250 is the default FabDigit quotes; the values on this page are for it.
Compare all 2 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
Porous forsterite | Choose for non-gas-tight, lower-cost insulating bodies, spacers and heater supports where open porosity and lower strength are acceptable. | 25 | 500 HV | 2 W/m·K | ||
C-250Default Dense forsterite | Choose for vacuum-tight metal/glass seals, microwave-tube and high-frequency insulators needing very low dielectric loss. | 65 | 750 HV | 4 W/m·K |
What is Mg2SiO4?
Mg2SiO4 (forsterite) is a magnesium silicate ceramic built on the olivine mineral base and supplied to IEC 60672 classes C-250 and C-240. It is chosen for good insulation resistance and a thermal expansion matched to certain sealing glasses and metals, and is produced as pressed, extruded or slip-cast insulators, bushings and seal rings. Density is 2.85 g/cm³, tensile strength is 65 MPa, thermal conductivity 3.5 W/m·K and maximum service temperature 1000 °C, and fired parts machine poorly (score 8). Where CTE matching is not required, steatite is the cheaper silicate option. Mg2SiO4 has a density of 2.85 g/cm³ (0.103 lb/in³), lighter than 79% of ceramic grades. It melts at 1,890°C (3,434 °F). Mg2SiO4 has a tensile strength of 65 MPa (9.43 ksi), weaker than 62% of ceramic grades. The elastic modulus is 130 GPa (18.9 Msi).
What is Mg2SiO4 used for?
- vacuum tube seals
- electrical insulators
- high-frequency insulation parts
Advantages
- Low embodied carbon — 2.6 kg CO₂/kg, better than 90% of ceramic grades
- Lightweight — 2.85 g/cm³ (0.103 lb/in³), better than 79% of ceramic grades
Limitations
- Hard to polish — 60/100, worse than 79% of ceramic grades
Mg2SiO4 properties
Typical room-temperature values for Mg2SiO4-C-250; bars are the position among ceramic grades.
Physical4
Mg2SiO4 has a density of 2.85 g/cm³ (0.103 lb/in³), lighter than 79% of ceramic grades. It melts at 1,890°C (3,434 °F).
Mechanical11
Mg2SiO4 has a tensile strength of 65 MPa (9.43 ksi), weaker than 62% of ceramic grades. The elastic modulus is 130 GPa (18.9 Msi).
Thermal5
Mg2SiO4 is rated for continuous service to 1,000°C (1,832 °F). It conducts heat at 3.5 W/m·K (2.02 BTU/hr·ft·°F), worse than 74% of ceramic grades. Thermal expansion is 9 µm/m·K (5 µin/in·°F).
Electrical5
Mg2SiO4 is an electrical insulator with a dielectric strength of 13 kV/mm (330.2 V/mil) and a resistivity of 1×10¹² Ω·m.
Chemical & Environmental2
Corrosion resistance is very good (75/100), better than 50% of ceramic grades.
Sustainability4
Producing a kilogram of Mg2SiO4 takes about 32 MJ of energy and emits 2.6 kg of CO₂ — less than 91% of ceramic grades. Typical recycled content is 0%.
Manufacturability3
Mg2SiO4's machinability is not recommended (8/100, better than 69% of ceramic grades).
Common Calculations4
Values are nominal handbook figures for design screening. Certified mill or lot data ships with every FabDigit order on request.
Strength versus weight in the ceramic family
Yield strength against density for every ceramic grade FabDigit runs. Mg2SiO4 is highlighted; hover a dot for its name, or open the interactive family chart.
Working with Mg2SiO4
Is Mg2SiO4 easy to machine?
Machine in the green or bisque state; fired bodies require diamond grinding/lapping and chip easily at edges.
Can Mg2SiO4 be welded?
Not weldable — joined by active-metal brazing (Ti/Zr-containing filler) or Mo–Mn metallizing plus Ni plating and brazing for vacuum-tight seals.
Can Mg2SiO4 be formed, bent or molded?
Dry pressing, isostatic pressing, extrusion or slip casting of talc/magnesia batches, then firing at ~1300–1450 °C with tight kiln control to avoid periclase or protoenstatite phases.
Mg2SiO4 chemical composition (wt %)
Limits by weight percent from the governing specification, written the way the spec states them — a single maximum for impurities, a range for alloying elements, and the base element as balance. Nominal is the typical mid-range value.
| Element | Spec limit (wt %) | Nominal |
|---|---|---|
| MgOforsterite stoichiometry 57.3 wt% MgO | 50 – 58 | 55 |
| Al2O3from clay/talc raw materials | 0 – 3 | 1 |
| CaO+BaOsintering aid / glassy bond | 0 – 3 | 1 |
| Fe2O3impurity, kept low for low dielectric loss | 0 – 0.5 | 0.2 |
| SiO2forsterite stoichiometry 42.7 wt% SiO2 | ≥ 38 (balance) |
What surface finishes work on Mg2SiO4?
Fired glazing improves surface resistivity and cleanability; metallized/plated pads used for brazing, otherwise lapped or diamond-polished.
How much does Mg2SiO4 cost?
Mg2SiO4 is a high-cost ceramic ($$$$), pricier than about 78% of the materials FabDigit quotes. Part price depends far more on geometry, tolerance and quantity than on the raw stock — upload a CAD file for a live quote.
Mg2SiO4 — frequently asked
What is Mg2SiO4 used for?
Mg2SiO4 is typically used for vacuum tube seals, electrical insulators and high-frequency insulation parts. In short: CTE-matched sealing ceramic; forsterite silicate insulator; 1000 °C service limit.
What is the tensile strength of Mg2SiO4?
Mg2SiO4 has a typical tensile strength of 65 MPa (9.43 ksi) — weaker than 62% of ceramic grades. Strength varies by condition: see the 2 listed tempers.
Is Mg2SiO4 easy to machine?
Not especially — machinability is rated not recommended (8/100, better than 69% of ceramic grades). Machine in the green or bisque state; fired bodies require diamond grinding/lapping and chip easily at edges.
Can Mg2SiO4 be welded?
Not weldable — joined by active-metal brazing (Ti/Zr-containing filler) or Mo–Mn metallizing plus Ni plating and brazing for vacuum-tight seals.
What surface finishes work on Mg2SiO4?
Fired glazing improves surface resistivity and cleanability; metallized/plated pads used for brazing, otherwise lapped or diamond-polished.
Can Mg2SiO4 be formed, bent or molded?
Dry pressing, isostatic pressing, extrusion or slip casting of talc/magnesia batches, then firing at ~1300–1450 °C with tight kiln control to avoid periclase or protoenstatite phases.
What is the maximum service temperature of Mg2SiO4?
Mg2SiO4 is rated for continuous use to about 1,000°C (1,832 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
How much does Mg2SiO4 cost?
Mg2SiO4 is a high-cost ceramic ($$$$), pricier than about 78% of the materials FabDigit quotes. Part price depends far more on geometry, tolerance and quantity than on the raw stock — upload a CAD file for a live quote.
Sources
- IEC 60672-3 Ceramic and glass insulating materials – Part 3: Specifications for individual materials (Types C-240, C-250) — IEC (1997)
- Engineered Materials Handbook Vol. 4: Ceramics and Glasses — ASM International (1991)
- Technical ceramics – steatite / forsterite product data — CeramTec / Kyocera (2023)
- Phase Diagrams for Ceramists – MgO–SiO2 system — American Ceramic Society (1985)
Property data is compiled from published supplier and standards handbooks and normalised for comparison; hardness values on non-Brinell scales are converted approximately for charting only. Manufacturability limits are FabDigit quote-engine defaults and may be relaxed by engineering review. Nothing on this page is a certification — request mill certs, CoC or material test reports with your order.