Macor-Machinable Glass Ceramic

Strict machining with an accuracy of up to 0.001mm can be achieved

Macor machinable glass ceramic developed by Corning is a high-performance polycrystalline composite material that is white throughout. Its most distinctive feature is that it has zero porosity and zero air leakage. It also has the ability to be processed by standard metal tools and is widely used in high-end manufacturing.

Macor Advantages

Easily machinable with standard metalworking tools.
Supports extremely tight machining tolerances, up to 0.0005 inches (0.013 mm).
Completely non-porous and suitable for vacuum applications without risk of outgassing.
No firing is required after machining, simplifying the manufacturing process.
High Precision: It allows for high dimensional accuracy and surface finish, making it ideal for applications requiring intricate parts.
Macor endures continuous use at temperatures up to 1000°C without degrading, ideal for high-temperature applications
Exhibits low thermal conductivity, making it an effective high-temperature insulator.
Macor is resistant to most chemicals, including acids, bases, and solvents, making it suitable for harsh chemical environments.
Strong and rigid, maintaining its shape without creeping or deforming, unlike high-temperature plastics.
Tailored Designs: Macor can be customized to meet specific industrial requirements, offering flexibility in design and application.
Material Compatibility: Macor can be easily combined with metals and glass, enhancing its versatility in various applications.

Macor Applications

Ultra-high vacuum systems, feedthroughs, and insulators.
Semiconductor equipment fixtures, insulators, and precision parts.
Mass spectrometers, ion traps, and low-temperature systems.
Surgical instruments, diagnostics, and imaging components.
Electric insulators in ion thrusters.
Electrode holders for plasma generators.
Structural supports for high-voltage equipment and transformers.
Precision coil formers (stable and high precision).
Spacers, cavities, and reflectors in laser assemblies.
Satellite system supports (thermally and electronically insulating)

Macor Material Properties

Thermal Properties

Thermal	SI/Metric	Imperial
CTE -100°C – 25°C	81 × 10⁻⁷ /°C	45 × 10⁻⁷ /°F
CTE 25°C – 300°C	90 × 10⁻⁷ /°C	50 × 10⁻⁷ /°F
CTE 25°C – 600°C	112 × 10⁻⁷ /°C	62 × 10⁻⁷ /°F
CTE 25°C – 800°C	123 × 10⁻⁷ /°C	68 × 10⁻⁷ /°F
Specific Heat, 25°C	0.79 kJ/kg·°C	0.19 Btu/lb·°F
Thermal Conductivity, 25°C	1.46 W/m·°C	10.16 Btu·in/hr·ft²·°F
Thermal Diffusivity, 25°C	7.3 × 10⁻⁷ m²/s	0.028 ft²/hr
Continuous Operating Temperature	800°C	1472°F
Maximum No Load Temperature	1000°C	1832°F

Mechanical Properties

Mechanical	SI/Metric	Imperial
Density	2.52 g/cm³	157 lbs/ft³
Porosity	0%	0%
Young’s Modulus, 25°C (Modulus of Elasticity)	66.9 GPa	9.7 × 10⁶ PSI
Poisson’s Ratio	0.29	0.29
Shear Modulus, 25°C	25.5 GPa	3.7 × 10⁶ PSI
Knoop Hardness, 100g	250 kg/mm²	—
Modulus of Rupture, 25°C (Flexural Strength)	94 MPa (Minimum specified average value)	13,600 PSI
Compressive Strength (After polishing)	345 MPa (up to 900 MPa)	49,900 PSI (130,000 PSI)

Electrical Properties

Electrical	SI/Metric	Imperial
Dielectric Constant, 25°C	—	—
1 kHz	6.01	6.01
8.5 GHz	5.64	5.64
Loss Tangent, 25°C	—	—
1 kHz	0.004	0.004
8.5 GHz	0.0025	0.0025
Dielectric Strength (AC) avg. (25°C, under 0.3 mm thickness)	45 kV/mm	1143 V/mil
Dielectric Strength (DC) avg. (25°C, under 0.3 mm thickness)	129 kV/mm	3277 V/mil
DC Volume Resistivity, 25°C	10¹⁷ Ohm·cm	10¹⁷ Ohm·cm

Note: This value is for reference only and may vary slightly depending on the batch conditions.

Machining Macor

Although Macor has the ability to process with standard metal tools, there are still some problems compared with metal (please check our latest machining guide for 2025). Ultra-precision machining can be achieved by using alloy milling cutters and correct machining parameters. For example, micro holes can be processed to 0.05mm, and internal threads can reach M1.4, but M1.4 needs to consider its practicality (it is recommended to be larger than M2). In addition, when processing threads, attention should be paid to edge collapse, which is recommended to be solved by chamfering. In terms of cooling, it is recommended to choose water-soluble coolant, which is not easy to adhere to the tool.

Jundro Ceramics is a professional precision manufacturer of Macor Machinable Ceramic materials. We specialize in utilizing our technical expertise and advanced equipment to process high-precision products. Our comprehensive service scope includes material selection, precision machining, surface treatment, and quality testing to ensure that each product can perform at its best in practical applications. If you would like to purchase Macor boards, rods, bars, tubes, or custom machined parts, please contact us

Macor Prototype Machining

Our video showcases the process of prototype machining for Machinable Glass Ceramic

Prototype Machining Case

We specialize in precision machining of Machinable Ceramic with complex shapes, and are able to achieve high-precision machining to meet the needs of various complex designs.

Related Materials and Consultation

Shapal-HI-M

High performance machinable aluminum nitride (AIN) ceramics—Shapal HI-M

Macor RoHS-Certified

Advanced material with RoHS certification – Macor Glass Ceramic

Frequently Asked Questions

How to Choose Between Shapal Hi M Soft and Macor?

1. Which material dissipates heat better? Shapal Hi M Soft has a high thermal conductivity of 90 W/(m·K), which is ideal for applications that require thermal conductivity. Macor is a thermal insulator (1.46 W/(m·K)) and is more suitable for applications that require insulation. 2. How do they perform under rapid temperature changes? Shapal can withstand thermal shock well and is reliable for components that are frequently exposed to heating and cooling cycles. But Macor is more prone to cracking in this case. 3. What is their maximum operating temperature? Shapal can withstand temperatures up to 1900°C in an inert atmosphere and up to 1000°C in air, making it suitable for extreme environments. Macor has a lower thermal limit, making it more suitable for medium-temperature applications. 4. Which material has higher strength? Shapal has higher flexural strength (300 MPa) and compressive strength (1200 MPa), making it ideal for high-stress applications. Macor is less durable, with a flexural strength of 94 MPa and a compressive strength of 345 MPa. 5. Is the cost difference big? Yes, when the performance of Macor meets the application requirements, it is more cost-effective and can save a lot of costs. 6. What factors should be considered when choosing? If your project involves high temperature, mechanical stress or thermal cycling, Shapal is a better choice. For budget-sensitive projects with moderate performance requirements, Macor is a practical choice.

What Is Macor Made Of?

Macor is a composite material consisting of fluorphlogopite (a type of mica) embedded in a borosilicate glass matrix, with the ratio of mica to glass being approximately 45% and 55%. This structure makes it both machinable and durable.

2. What are the main chemical components of Macor?

The composition of Macor is:

3. How does its microstructure enhance its machinability?

The random microcrystalline structure of Macor enables precision machining. The tool can remove micrometer-level material without causing cracks or breaks, thus achieving tight tolerances.

4. Why does Macor use borosilicate glass?

Borosilicate glass offers thermal stability, chemical resistance, and structural support similar to applications in test tubes and labware, such as Pyrex®.

5. What are the benefits of this composition?

The unique combination of mica and borosilicate glass enables Macor to:

Be highly machinable using standard tools.

Have thermal and electrical insulating properties.

Resistant to high temperatures and a wide range of chemical environments.

What Size of Macor Products Can We Process?

Corning currently only offers two sizes of Macor materials: 330*350*57mm (approximate size) and φ76mm*317mm. Junjie
The Ceramics Department has extensive experience in processing Macor machinable ceramics and can process the full range of products in the above two sizes.
We have 11 high-precision ceramic CNC machining centers and one five-axis machining center. The Macor ceramic products we process include: ion trap lens brackets, quadrupoles
Ceramic brackets, insulators, etc.

Processing accuracy
Flatness: 0.001mm
Dimensional tolerance: 0.001mm
Roughness: Ra0.01um

What Are Glass Ceramic Materials?

Glass ceramics are materials that combine the properties of glass and ceramics, made through a controlled crystallization process. Common types include:

1. Mica-based glass ceramics
Example: Macor.
Features: Machinable, electrically insulating, low thermal conductivity.

2. Lithium disilicate glass ceramics
Applications: Dental restorations, optical components.
Features: High strength, good transparency, wear resistance.

3. Aluminosilicate glass ceramics
Applications: Cookware, aviation components, electronics.
Features: Thermal shock resistance, high temperature resistance.

4. Spinel-based microcrystalline glass
Uses: Transparent armor, optical devices.
Features: High strength, optical transparency.

5. Apatite-based glass ceramics
Applications: Bioceramics for bone and tooth restorations.
Features: Good biocompatibility, strong adhesion to tissues.

6. Zirconia-based glass ceramics
Applications: Crowns, cutting tools.
Features: Tough, wear-resistant, thermally stable.
Glass-ceramics have a wide range of uses and are used in aerospace, healthcare, electronics and consumer products.

Is Macor Ideal for Prototyping?

1. Can Macor be used for prototyping?
Yes, Macor is well suited for prototyping due to its machinability and ability to achieve tight tolerances.

2. What are the advantages of using Macor for prototyping?
Easy to process: Rapid prototyping with standard tools.
Cost-effective: More affordable than other advanced ceramics.
Fast turnaround: Great for quick iterations and adjustments.

3. What types of prototypes are suitable for Macor?
Macor is well suited for high temperature applications, electrical insulation, and mechanical parts.

4. Are there any limitations?
Macor may not be suitable for prototypes that require high mechanical strength or impact resistance.

5 key Techniques For Macor Ceramic Processing

How to choose the right tool for Macor ceramic machining?
When machining Macor, it is recommended to use carbide tools because they have good wear resistance and high temperature stability. Using the right tool can ensure machining accuracy and surface quality and avoid premature wear of the material.
What is the best machining method for Macor?
Macor can be machined by traditional machining methods such as turning, milling, drilling and grinding. To ensure machining quality, it is recommended to use slow cutting speed and suitable coolant to reduce thermal stress and material cracking.
How to avoid cracks during machining?
Since Macor is a brittle material, drastic temperature changes should be avoided as much as possible during machining. Using stable cutting parameters and sufficient coolant can reduce thermal stress and avoid cracking.
How to deal with thermal stress during machining?
During machining, thermal stress may cause the material to break or deform. In order to reduce thermal stress, using sufficient coolant and lower cutting speed while maintaining a stable machining temperature can effectively reduce the impact of thermal stress.
How to ensure the machining accuracy of Macor ceramics?
The machining accuracy of Macor ceramics can usually reach ±0.0005 inches (0.013 mm). To ensure high-precision machining, high-quality tools should be used and the machine settings should be strictly controlled to avoid vibrations and errors.

How is the electrical insulation of macor?

Macor is a glass-ceramic material with excellent electrical insulating properties. Its volume resistivity is typically between 10¹² and 10¹⁴ ohm-cm, comparable to alumina and other ceramic materials. Due to its non-porous structure and moisture absorption of less than 0.01%, Macor maintains its insulating properties even under high temperature and humidity conditions.

How is the chemical resistance of Macor?

Macor has a small mass loss in weak acid (such as dilute nitric acid) and neutral salt solution, and the acid resistance level is "4", which is above average and can meet most industrial needs.
In weak alkaline environment (such as 0.1 N NaOH), the mass loss is greater than that in acidic environment.
In strong alkaline environment (such as 5% NaOH, high temperature and high concentration), long-term use will cause Macor to have a significant mass loss of 100 mg/cm² or even greater, which will affect the material mechanics and structural integrity.