Magnesium Oxide Rods are solid ceramic components made primarily from sintered magnesium oxide (MgO). They are designed to combine high electrical insulation, excellent thermal conductivity, and resistance to high temperatures and chemical corrosion. These rods are widely used in both industrial heating systems and laboratory furnaces, serving as insulating and structural elements in high-temperature environments.
Magnesium Oxide Rod Benefits
- Dual-Purpose Design — suitable for electric heating systems and laboratory analytical furnaces.
- High-Temperature Endurance — stable performance up to 1900 °C without deformation or conductivity loss.
- Precise Dimensional Control — OD/ID tolerance within ±0.05–0.1 mm ensures perfect coaxial alignment.
- Corrosion Resistance — inert to molten metals, alkalis, and chlorides under operating conditions.
- Thermal Conductivity Balance — efficiently transfers heat while maintaining electrical insulation integrity.
Mgo Rod Properties
|
Properties |
Unit |
Value |
|
Material |
% |
99 MgO |
|
Density |
g/m³ |
3.5 |
|
Bulk Density |
g/m³ |
2.8 |
|
ApparentPorosity |
% |
20 |
|
Compressive Strength |
MPa |
50 |
|
FlexuralStrength |
MPa |
16 |
|
Refractoriness |
SK |
42< |
|
Thermal Conductivity |
W/(m.K) |
5 |
|
Coefficient of thermal expansion (20～1000℃) |
10-6/K |
13 |
|
Operating temperature |
Max (℃) |
2200 |
|
Room temperature |
Room temperature (℃) |
1800 |
Magnesia Rods Specifications
Magnesia Rod Packaging
- Each rod is individually wrapped in foam or bubble film
- Bulk packed in reinforced cardboard boxes with foam
Applications of Magnesium Oxide Rod
MgO rods serve as essential insulating and structural materials in industrial heating systems, laboratory analytical equipment, and metallurgical processes. Their unique combination of thermal conductivity, dielectric strength, and chemical inertness enables reliable performance across multiple high-temperature environments.
-
Industrial Heating and Thermal Processing Equipment
✅Key Advantages
1. Provides electrical insulation >10¹² Ω at 25 °C, preventing current leakage in cartridge and tubular heaters.
2. Maintains structural integrity at temperatures up to 1900 °C, resisting cracking or deformation under cyclic heating.
3. Enables uniform heat transfer and consistent thermal profiles within heating assemblies.
✅ Problem Solved
A U.S. heating-element manufacturer replaced alumina cores with high-purity MgO rods in 8 kW cartridge heaters. As a result, product lifetime increased by 45 %, insulation failures dropped by over 35 %, and power efficiency improved due to better heat distribution.
-
Laboratory Furnaces, TGA/DSC Instruments, and Analytical Systems
✅Key Advantages
1. Stable thermal expansion coefficient (8–12 × 10⁻⁶ / °C) ensures dimensional stability during rapid heating cycles.
2. Chemical inertness prevents sample contamination in analytical testing.
3. Compatible with TGA/DSC, tube furnaces, and micro-heaters, enabling repeatable and precise thermal measurements.
✅ Problem Solved
A German analytical instrument OEM integrated MgO rods as support elements in their DSC systems. After the switch, calibration drift was reduced by 30 %, and thermal stability improved enough to extend maintenance intervals from 6 months to 1 year.
-
Metallurgical, Refractory, and High-Temperature Material Processing
✅Key Advantages
1. Non-wetting surface resists adhesion of molten metals, slags, and glass melts.
2. Excellent resistance to alkali vapor and chloride corrosion under oxidizing and reducing atmospheres.
3. Serves as a structural support or spacer in crucibles, reaction tubes, and sintering trays.
✅ Problem Solved
A Korean steel R&D lab employed MgO rods in continuous-firing furnaces for high-Ni alloys. The components maintained geometry after 250 thermal cycles (1200–1800 °C), eliminating 12 % annual downtime previously caused by refractory failure.
Magnesium Oxide Rod Usage Instructions
Proper installation, gradual heating, and moisture control can extend the service life of magnesium oxide rods by 30–50 %, reducing maintenance costs and improving overall system reliability.
-
Installation
1. Check fit and tolerance: Ensure both ends of the MgO rod fit precisely into the heater or furnace assembly according to specified tolerances. Loose installation may cause vibration wear; overly tight installation can induce micro-fractures.
2. Maintain coaxial alignment: Align the rod axially with surrounding parts to prevent bending stress during thermal expansion.
3. Avoid excessive force: Insert gently without twisting or pressing; MgO ceramics have limited flexural strength.
4. Use proper supports: For long rods (>300 mm), use intermediate ceramic brackets to reduce bending stress under self-weight.
-
Usage
1. Temperature control: Operate within rated limits—ideally below 1900 °C continuous exposure. Short-term overloads are acceptable only if ramping is slow and uniform.
2. Heating and cooling rate: Maintain gradual temperature changes (≤ 5 °C/s) to avoid thermal shock and internal stress.
3. Atmosphere compatibility: Suitable for air, vacuum, argon, or nitrogen environments; avoid direct exposure to reducing hydrogen or sulfur gases that may react with MgO.
4. Electrical performance: Ensure the rod is dry and free from contaminants before power-up to maintain insulation resistance > 10¹² Ω.
-
Storage
1. Environment: Store in a dry, clean, and dust-free area with humidity below 60 % RH to prevent surface hydration or cracking.
2. Packaging: Keep original foam and plastic wrapping if possible; these protect against moisture absorption during long-term storage.
3. Separation: Avoid contact with metals, acids, or hygroscopic materials that could cause surface reactions or staining.
4. Long-term storage: For storage beyond 12 months, re-dry components at 120 °C for 1–2 hours before use to restore insulation performance.
-
Cleaning
1. Routine maintenance: Use compressed air or 99 % ethanol to remove dust and surface deposits before installation.
2. Avoid immersion: Do not submerge in water or alkaline cleaners—MgO absorbs moisture and may form Mg(OH)₂, degrading performance.
3. Post-use cleaning: If used in a metal-rich or oxidizing environment, gently polish residue using a fine alumina pad to restore surface integrity.
-
Cautions
1. Avoid mechanical shock or vibration during heating or cooling, as MgO ceramics are strong under compression but brittle under impact.
2. Handle polished or machined surfaces with gloves to prevent oil contamination, which may reduce insulation resistance.
3. Inspect periodically: Replace rods showing cracks larger than 0.2 mm, warping > 0.5 mm, or any visible surface discoloration due to chemical attack.
4. Do not expose to rapid flame impingement or localized heating—always use uniform thermal zones.
5. Avoid reusing damaged rods; compromised parts may cause insulation failure or equipment short-circuiting.
