High Voltage Customized Electrical Alumina Ceramic Insulators for Industry
Specification and production capability of alumina ceramic insulator
Grade of material | 75%, 85%, 90%, 96% , 99%, 99.5% and 99.8% alumina |
Outer diameter | 0.5 ~500 mm |
Length | 1 ~ 1000mm |
Roughness | To be Ra0.1 | Roundness | To be 0.005mm |
Surface treatment | Polished, Glazed, Metalized availability |
Cosmetic quality | Smooth surface without no contamination, deformation, and crack |
The accuracy achieved after precision machining
(1) Axis: roundness 0.002 mm, concentricity 0.002 mm, smoothness Ra0.1;
(2) Hole: the minimum processing hole diameter is 0.2 mm and the depth is up to 6 mm (depending on the material);
(3) Slot: min. value to be 0.1 mm of narrow groove, and grooves with custom shapes;
(4) Plane: 0.1mm sheet with minimum processable thickness, parallelism 0.001mm, measurement tolerance 0.001 mm, finish Ra0.1;
(5) Thread: The minimum machinable M2 internal thread, the accuracy of GB-7h, the external thread size is not limited, the accuracy is GB-6g.
Main characteristics of the alumina ceramic insulator
1. High electrical resistivity: used in all-electric products, electric heating products, and wear-resistant machinery parts.
2. Extreme high insulation, it can withstand 18KV at mm2 at least. With glazed treatment, it will increase the insulation.
3. They offer different grade dimensional accuracy per sintered only, precision machining
4. They are more cost-effective ceramic parts with equivalent performance among all other technical ceramics
5. High hardness, it is can be up to 1700 HV, and Super compressive strength up to 2240 Mpa
6. High heat resistance: Alumina ceramic parts offer excellent thermal stability, which means that it is widely used in areas where resistance to high temperatures is essential.
7. Good wear resistance: it is an ideal choice to wear parts in high abrasive industry
8. High corrosion resistance: It is insoluble in water and only slightly soluble in strong acid and alkaline solutions. Good chemical stability of alumina leads to high corrosion resistance.
9. We support a variety of customized alumina ceramic parts base on customer's drawing, sample, or reference parameters
Description of alumina ceramic insulator
Alumina ceramic is one of structural ceramics, with high insulation breakdown, high voltage resistance, high strength, good thermal conductivity, dielectric loss, and corrosion resistance. Due to alumina is more cost-effective among all technical ceramics, alumina ceramic insulators are commonly used in electronic ceramic substrates, high voltage/current electrical insulation, vacuum devices, devices porcelain, spark plugs and other products.
Our factory produces a selection of purity of alumina from 75% to 99.8%, all of the ceramic parts we supplied are with a dense body via dry pressing, hot pressing, ceramic injection molding, and ISO pressing. In order to achieve some special application for fitting, reducing the friction, increasing the insulation, we provide a serial of secondary processes after sintering, covering CNC machining, polishing, glazing and metallizing.
We manufacture a wide range of alumina ceramic rings, including ceramic tubes, ceramic rings, ceramic disc, ceramic rod, ceramic arms, ceramic wire guides. Whatever, its a prototyping case, or high volume demand, we believe we are able to provide you a desirable solution.
Application of alumina ceramic insulator:
Alumina ceramic parts are widely used in the electronic, electrical, machinery, chemistry, ceramic seal, mineral, new energy, military, aerospace, almost all modern industries.
Datasheet of technical ceramic materials
Property | Units | Materials |
99.5%Al2O3 | 99%Al2O3 | 95%Al2O3 | ZrO2 | Si3N4 |
Density | g/cm3 | ≥3.85 | ≥3.80 | ≥3.60 | ≥6.0 | ≥3.2 |
Water absorption | % | 0 | 0 | 0 | 0 | 0 |
Hardness | HV | 1700 | 1700 | 1500 | 1300 | 1550 |
Flexural strength | Mpa | ≥379 | ≥338 | ≥320 | ≥1200 | ≥600 |
Compressive strength | Mpa | ≥2240 | ≥2240 | ≥2000 | ≥1990 | ≥2500 |
Fracture toughness | Mpa m1/2 | 4-5 | 4-5 | 3-4 | 6.5-8 | 6 |
Max. service temperature (Non-loading) | ℃ | 1675 | 1600 | 1500 | 1000 | 1200 |
CTE (20-800℃) | 1×10 -6 /℃ | 6.5~8.0 | 6.2~8.0 | 5.0~8.0 | 8.0~9.5 | 3.1 |
Thermal shock | T(℃) | ≥250 | ≥200 | ≥220 | ≥300 | ≤1000 |
Thermal conductivity(25℃) | W/m.k | 30 | 29 | 24 | 3 | 15~20 |
Volume resistivity (25℃ ) | ohm.cm | >1 x 10 14 | >1 x 10 14 | >1 x 10 14 | >1 x 10 11 | >1 x 10 12 |
Insulation strength | KV/mm | 19 | 18 | 18 | 17 | |
Dielectric constant(1Mhz) | (E) | 9.7 | 9.5 | 9.5 | 29 | |
Packaging proposal and transportation solutions
1. We will keep the ceramic parts inside the inner package to be fixed without moving, then it will prevent them from collision each other, to avoid any cause any chippings during transportation.
2. In addition, the inside of the outer carton will be filled with sufficient protective kinds of stuff.

Why choose us?
★ 10+ Years of manufacturing experience in OEM, ODM ★ Powerful R&D, mass production capability
★ In-house comprehensive manufacturing types of equipment ★ Rigorous quality control system and processes
★ Surpassing pre-sales and after-sales service ★ Abide all orders as the first priority
FAQs (Frequently Asked Questions)
Q1. Are you a factory or trading company?
A: We are a manufacturer. You are welcome to visit our factory.
Q2: Do you send a sample to check?
A: Sure, the sample is free and freight collect.
Q3: When will you ship it?
A: If the products are in storage, we'll ship within 48 hours
Q4: When can I get the price?
A: We regularly quote within 24 hours after we get your inquiry. If you are in urgent need of getting the price.
Please call us or tell us in your email so that we will proceed with your inquiry as a priority.
Q5: Is it available to provide customized products?
A: We always support custom-made demand as per different materials, dimensions, and designs.
Q6: How to ensure quality?
A: The dimension out of any batch will be carried out sampling inspection per international AQL standard. A 100% cosmetic inspection will be done.
Q7: What other products are you dealing with?
A: We focus on a variety of ceramic tubes, ceramic substrates, ceramic sheets, textile ceramics besides metalized ceramics.