What are the standard properties of alumina industrial ceramics?
The hardness of alumina industrial ceramics is very large, and its Rockwell hardness is HRA80-90. The hardness is second only to diamond and far exceeds the wear resistance of wear-resistant steel and stainless steel. So what are the standard properties of alumina industrial ceramics?
Standard performance of alumina industrial ceramics
1. The bulk density of alumina industrial ceramics
The volume density of alumina industrial ceramic structural parts has a great relationship with the choice of raw materials and the porcelain making process. According to the national standard GB/T5593-1999, the volume density of alumina industrial ceramic products is required to be above 3.60g/cm3.
2. Air tightness of alumina industrial ceramics
Alumina industrial ceramic products require high vacuum air tightness. According to the electronic industry standard SJ/T11246, the air leakage rate of the sealing parts is QK≤1×10-11PaM3/S, so the alumina industrial ceramic structure is specified The air leakage rate of the piece itself must also meet the above standards to meet the relevant use of the material.
Alumina Industrial Ceramic Plate
3. Dielectric constant of alumina industrial ceramics
The dielectric constant of alumina industrial ceramics refers to a value of the degree of dielectric polarization of an insulating material under an alternating electric field. It is the ratio of the capacitance of a capacitor filled with insulating material to a capacitor of the same electrode size when a vacuum is used as the medium.
4. Tangent value of dielectric loss angle of alumina industrial ceramics:
The dielectric loss of alumina industrial ceramics refers to the loss of electrical energy due to polarization or absorption of insulating materials under the action of an alternating electric field.
Generally, there is heat generation on the dielectric material. The dielectric loss of alumina industrial ceramics is expressed by the tangent of the dielectric loss angle.
Alumina Industrial Ceramic Sleeve
5. Linear expansion coefficient of alumina industrial ceramics
The relative elongation of alumina industrial ceramics when the unit temperature is increased is the average linear expansion coefficient, which is one of the important performance indicators of alumina industrial ceramic structures.
As alumina industrial ceramic structural parts often need to be sealed with metal parts, it is required that the expansion coefficient match that of the metal material.
6. Breakdown strength of alumina industrial ceramics:
The breakdown strength of alumina industrial ceramic insulation material refers to the change of the material under the action of external direct current, which is mainly caused by the change of the internal structure. When the direct current strength reaches a certain value, the internal structure of the material is promoted to change and breakdown occurs.