Alumina Plate

Alumina plates are dense materials, and they have four types: 95%alumina plate, 96% alumina plate, 99% alumina plate and 99.8% alumina plate.

Alumina Plate with 95% Al2O3

Alumina Plate with 96% Al2O3

Alumina Plate with 99% Al2O3

Alumina Plate with 99.8% Al2O3

Common Sizes of Alumina Plates

The above sizes are the existing mold sizes. If you need plates of different sizes, a small amount can be cut by machine to get the desired size. If the quantity is large, you can develop a new mold to do it. The cost of the mold depends on the size of the plate, and it is about 500 - 1,500 dollars.

Performance Comparison of Alumina Plates

95% alumina plate has excellent wear resistance, hardness ≥ HRA85, second only to the hardness of diamond. The surface is smooth and the friction coefficient is small. Its wear resistance is very ideal, especially in high temperature oxidizing media or corrosive media, the performance of ceramic plate material is much superior than other metal materials. Moreover, 95% alumina plate has much better wear resistance than the 90% wear-resistant lining on the market, because the more alumina content, the better the wear resistance. Additionally, the price of 95% alumina plate is lower than that of 99% alumina plate, which can save costs.

96% alumina plate has the main advantages of high temperature resistance, excellent electrical insulation performance, low dielectric constant and dielectric loss, high thermal conductivity, good chemical stability, and similar thermal expansion coefficient to components. Plates with a thickness of 0.25-1.0mm will be formed by tape casting, and those with a thickness greater than 1.0mm will be formed by dry pressing. The forming methods are different, but the using effect is the same. Because the molding process is relatively simple, the cost of the product is low as well, but the alumina ceramic substrate also has disadvantages such as brittleness and a small substrate area.

99% alumina plate has outstanding high temperature strength and high load capacity, which can increase the efficiency of furnace space usage. It has no deformation and cracks after long-term use, no corrosion to products and the molten metal cannot wet the alumina setter. 99% alumina plate can be used in protective and reducing atmospheres. It is also stable in reactive and hydrogen atmospheres. Its surface is flat and smooth, the size is controlled precisely, and various grooves and platform surfaces can be processed.

Features

High hardness: Alumina sheet is outstanding in wear resistance and appropriate for producing wear-resistant components since it is second only to diamond in hardness.

High wear resistance: Alumina sheet is ideal for producing wear-resistant components such abrasives and sliding bearings because of its great hardness, which wears relatively little during friction.

High temperature resistance: Industrial applications requiring high temperatures up to 1800°C find alumina sheet to be the perfect material.

Electrical insulation: For components insulating in the electronics sector, alumina sheet is a great electrical insulation material with high resistance and low dielectric constant.

Chemical stability: Suitable for use in harsh situations, alumina sheet resists most acids and alkalis well and is not easily reacted to chemically.

Low thermal expansion coefficient: When the temperature fluctuates, the low thermal expansion coefficient of alumina sheet helps to preserve dimensional stability.

Large mechanical loads may be supported by the high compressive strength of alumina sheet.

Transparent ceramic components may be made using certain high-purity alumina sheets because of their excellent light transmittance.

Biocompatibility: Artificial joints are only one use for the excellent biocompatibility of alumina sheets in the medical industry.

ecologically benign: An ecologically benign material, alumina sheets don't release any toxic chemicals during manufacture.

Customers can comprehensively compare the properties of the above materials, choose materials suitable for your application, or consult our technical staff to discuss related material issues.

Forming Methods and Machining

95% and 99% alumina plates are formed by dry pressing using a fully automatic press, which can produce high pressure and uniform impact, forming a dense ceramic green body. The tungsten steel mold used makes the pressed ceramic green body not easy to deform.

96% alumina plates are mainly produced by tape-casting. The alumina ceramic powder is uniformly mixed with a specific solvent to form a green film. The green film is dried to form a green sheet with a certain strength and flexibility, and then cut and punched according to the required shape, and finally the finished product is obtained through degreasing and sintering.

99.8% is generally formed by isostatic pressing to improve product compactness. The static pressure molding method is to put alumina powder into an elastic mold and seal it, and then put the mold into a container filled with high-pressure gas or liquid. After sealing, the powder is pressed into a green body with higher density by using the characteristics of equal three-dimensional force.

The alumina plates formed by dry pressing and isostatic pressing are sintered and then finely ground by a double-sided grinder to ensure that the surface of the plate is smooth and delicate. The surface of tape-cast alumina plate itself is smooth and delicate, and the roughness after molding is between Ra0.3-0.7um. If surface polishing is required, we will use harder abrasive polishing materials for finishing, usually by grinding from coarse to fine abrasives step by step, and finally surface polishing. In terms of size cutting, the sheet with a thickness of 0.25-2.0 will be cut by laser, and the thickness above 2.0mm will be cut by grinding wheel. There are also suitable machines for processing to meet the requirements of digging and drilling.