High-Purity 99% Alumina Ceramic Rods and Tubes

Typical Specifications

High-Purity 99% Alumina Ceramic Rods

TecCera supplies precision ceramic rods manufactured from high-purity alumina containing at least 99% Al₂O₃. These rods combine high hardness, excellent wear resistance, electrical insulation, dimensional stability, and reliable performance at elevated temperatures.

Compared with many conventional metal components, alumina ceramic rods provide electrical insulation, corrosion resistance, and reduced wear without requiring protective coatings. They are widely used as insulating supports, wear-resistant shafts, plungers, guides, positioning pins, and structural components in electrical, mechanical, semiconductor, laboratory, and thermal-processing equipment.

Custom diameters, lengths, profiles, tolerances, and surface finishes are available according to customer drawings or samples.

Key Features

High Hardness and Wear Resistance

With a Mohs hardness of approximately 9, high-purity alumina offers excellent resistance to abrasion and surface wear. Precision-ground or polished rods are suitable for shafts, plungers, guides, sliding components, and other applications requiring long-term dimensional stability.

Elevated-Temperature Stability

Alumina retains useful mechanical and electrical properties at elevated temperatures and has a relatively low coefficient of thermal expansion. Depending on the material grade, applied load, atmosphere, and operating cycle, the maximum service temperature may reach approximately 1700°C.

Rapid heating and cooling should be avoided unless the component has been specifically designed and validated for thermal cycling.

Excellent Electrical Insulation

High-purity alumina provides high electrical resistivity, good dielectric strength, and low dielectric loss. It is suitable for insulating rods, electrode supports, heater supports, feedthrough components, and high-voltage electrical equipment.

Chemical and Oxidation Resistance

Alumina resists oxidation and many commonly used chemicals, making it suitable for laboratory, chemical-processing, and industrial equipment. Compatibility should be evaluated separately for concentrated acids, strong alkalis, molten salts, and high-temperature corrosive media.

Precision Machining and Customization

Ceramic rods can be manufactured with controlled diameter, length, straightness, dimensional tolerance, and surface roughness. Available finishing operations include precision grinding, cutting, drilling, slotting, chamfering, lapping, and polishing.

Typical Applications

Semiconductor and Electronics

• Electrical insulating supports
• Electrode and heater supports
• Semiconductor-equipment fixtures
• High-voltage insulating components
• Precision positioning and handling components

High-Temperature Equipment

• Heating-element supports
• Furnace positioning components
• High-temperature electrical insulation
• Kiln and thermal-processing equipment parts

Mechanical Engineering

• Wear-resistant shafts
• Ceramic plungers
• Precision guide rods
• Positioning and locating pins
• Sliding and bearing components

Chemical and Laboratory Equipment

• Corrosion-resistant support components
• Analytical instrument parts
• Laboratory equipment components
• Fluid-handling and processing equipment parts

Frequently Asked Questions

1. What is the maximum service temperature of a 99% alumina ceramic rod?

Depending on the alumina grade, applied load, atmosphere, component dimensions, and heating cycle, the maximum service temperature may reach approximately 1700°C.

Continuous operating temperature is normally lower than the maximum short-term temperature. Please provide your actual operating conditions so that the appropriate material grade can be evaluated.

2. Can 99% alumina ceramic rods be custom machined?

Yes. We support custom diameters from 3 to 50 mm and lengths up to 2500 mm, subject to the required diameter, straightness, tolerance, and transportation conditions.

Available machining services include precision grinding, cutting, drilling, slotting, chamfering, lapping, and polishing. Please provide a drawing or sample for manufacturability review and quotation.

3. Can alumina rods be manufactured with axial holes?

Yes, depending on the dimensions and required geometry. However, components with continuous axial holes are generally classified as alumina ceramic tubes rather than solid ceramic rods.

Single-hole, multi-hole, and special-profile ceramic components can be evaluated according to customer drawings.

4. What is the difference between alumina and zirconia ceramic rods?

Alumina ceramic rods generally provide higher hardness, excellent electrical insulation, good high-temperature stability, and lower material cost.

Zirconia ceramic rods provide greater fracture toughness and resistance to mechanical impact. Alumina is typically preferred for insulation, hardness, wear resistance, and high-temperature applications, while zirconia is more suitable for components exposed to impact, bending, or higher mechanical stress.

5. What information is required for a quotation?

Please provide:

• Technical drawing or reference sample
• Required alumina purity
• Diameter and length
• Dimensional and straightness tolerances
• Surface-roughness requirement
• Operating temperature and atmosphere
• Mechanical load and chemical exposure
• Required quantity

Send us your drawing or application requirements for material evaluation, manufacturability review, and quotation.