Macor · print state · default condition
Macor As Fired
Properties of the As Fired condition, compared with the other Macor tempers.
Standard supply condition: fully ceramized rod, plate or block ready for direct machining to final dimensions with no post-fire shrinkage.
What is Macor As Fired?
Macor As Fired is Macor in the As Fired condition — standard supply condition: fully ceramized rod, plate or block ready for direct machining to final dimensions with no post-fire shrinkage. Macor As Fired has a tensile strength of 34 MPa (4.93 ksi), weaker than 72% of ceramic grades. Elongation at break is 0% and the elastic modulus is 66.9 GPa (9.7 Msi). Macor As Fired has a density of 2.52 g/cm³ (0.091 lb/in³), lighter than 81% of ceramic grades.
Advantages
- Easy to machine — 60/100, better than 89% of ceramic grades
- Lightweight — 2.52 g/cm³ (0.091 lb/in³), better than 81% of ceramic grades
- Good corrosion resistance — 88/100, better than 76% of ceramic grades
Limitations
- Poor heat conductor — 1.5 W/m·K (0.844 BTU/hr·ft·°F), worse than 92% of ceramic grades
- Hard to polish — 55/100, worse than 86% of ceramic grades
- Low stiffness — 66.9 GPa (9.7 Msi), worse than 83% of ceramic grades
Macor As Fired properties
Typical room-temperature values for Macor As Fired — 6 properties are specific to this condition; the rest are grade-level values shared by every Macor temper. Each bar shows where the value sits among the ceramic grades in FabDigit's library — further right is higher.
Physical2
Macor As Fired has a density of 2.52 g/cm³ (0.091 lb/in³), lighter than 81% of ceramic grades.
Mechanical12
Macor As Fired has a tensile strength of 34 MPa (4.93 ksi), weaker than 72% of ceramic grades. Elongation at break is 0% and the elastic modulus is 66.9 GPa (9.7 Msi).
Thermal5
Macor As Fired is rated for continuous service to 800°C (1,472 °F). It conducts heat at 1.5 W/m·K (0.844 BTU/hr·ft·°F), worse than 92% of ceramic grades. Thermal expansion is 9.3 µm/m·K (5.17 µin/in·°F).
Electrical5
Macor As Fired is an electrical insulator with a dielectric strength of 40 kV/mm (1,016 V/mil) and a resistivity of 1×10¹⁴ Ω·m.
Chemical & Environmental2
Corrosion resistance is excellent (88/100), better than 76% of ceramic grades.
Sustainability3
Producing a kilogram of Macor As Fired takes about 70 MJ of energy and emits 5.5 kg of CO₂ — less than 70% of ceramic grades. Typical recycled content is 0%.
Manufacturability2
Macor As Fired's machinability is good (60/100, better than 89% 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.
Working with Macor As Fired
Is Macor easy to machine?
Machine dry with sharp carbide or diamond-coated tooling at moderate speed and light feed; holds ±0.013 mm and 0.5 µm Ra without any post-fire step — chip out at through-hole exits is the main risk.
Can Macor be welded?
Not weldable; join by metallizing and brazing, glass frit sealing, or high-temperature ceramic adhesive/mechanical clamping.
Can Macor be formed, bent or molded?
Supplied as ceramized rod/plate/block only — no plastic forming; net shape is obtained entirely by subtractive machining.
What surface finishes work on Macor?
Lap and polish with diamond or SiC media for flatness/sealing surfaces; can be metallized (Ti/Mo-Mn, sputtered Au/Cr) for electrodes and vacuum feedthroughs.
Macor 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 |
|---|---|---|
| SiO2silica | 44 – 48 | 46 |
| MgO | 16 – 18 | 17 |
| Al2O3 | 15 – 17 | 16 |
| K2O | 9 – 11 | 10 |
| B2O3 | 6 – 8 | 7 |
| Ffluorine, forms fluorophlogopite mica crystals | 3 – 5 | 4 |
Macor As Fired — frequently asked
What is Macor As Fired used for?
Macor As Fired is typically used for vacuum chamber feedthroughs and insulators, probe holders and test fixtures, semiconductor process fixtures, high-voltage standoffs and spacers, spacecraft insulating components and aerospace radomes. In short: easily machined glass-ceramic.
What is the tensile strength of Macor As Fired?
Macor As Fired has a typical tensile strength of 34 MPa (4.93 ksi) — weaker than 72% of ceramic grades.
Is Macor As Fired easy to machine?
Reasonably — machinability is rated good (60/100, better than 89% of ceramic grades). Machine dry with sharp carbide or diamond-coated tooling at moderate speed and light feed; holds ±0.013 mm and 0.5 µm Ra without any post-fire step — chip out at through-hole exits is the main risk.
Can Macor As Fired be welded?
Not weldable; join by metallizing and brazing, glass frit sealing, or high-temperature ceramic adhesive/mechanical clamping.
What surface finishes work on Macor As Fired?
Lap and polish with diamond or SiC media for flatness/sealing surfaces; can be metallized (Ti/Mo-Mn, sputtered Au/Cr) for electrodes and vacuum feedthroughs.
Can Macor As Fired be formed, bent or molded?
Supplied as ceramized rod/plate/block only — no plastic forming; net shape is obtained entirely by subtractive machining.
What is the maximum service temperature of Macor As Fired?
Macor As Fired is rated for continuous use to about 800°C (1,472 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
Can FabDigit make parts in Macor As Fired?
Yes — Macor As Fired is available for CNC machining with instant online pricing. Upload a STEP file to get a price and a DFM check.
Sources
- MACOR Machinable Glass Ceramic — Product Information — Corning Incorporated (2012)
- Engineered Materials Handbook Vol. 4: Ceramics and Glasses — ASM International (1991)
- Glass-ceramic property data (mica glass-ceramics) — MatWeb / Ceramic supplier data sheets (2023)
Property data is compiled from published supplier and standards handbooks and normalised for comparison. Nothing on this page is a certification — request mill certs, CoC or material test reports with your order.