What factors affect the light transmittance of alumina ceramics (tubes, rods)

Factor 1: Organizational structure of raw materials

Transparency is a key property of alumina ceramics (tubes, rods), which depends not only on the basic chemical composition of the material but also on the microstructure of the material.So, alumina ceramics (tube, bar) how transparent also depends on the ceramic porosity, grain size, grain boundary structure and surface finish and other factors.

Factor 2: Production engineering

The preparation process of alumina ceramics (tubes and rods) is essentially to completely exclude the densification process of microscopic pores in the sintering process, and the size, number and type of pores in the materials will have a significant impact on its transparency.In addition to the porosity, the diameter of the pores also has a great influence on the light transmittance of alumina ceramics (tubes and rods). When the diameter of pores is the length of the incident light wave, the transmittance is the lowest.

The crystal size of alumina ceramic (tube, bar) polycrystals also has a great influence on the light transmittance. When the wavelength of incident light is equivalent to the grain diameter, the light scattering effect is the largest and the light transmittance is the lowest.In view of this, in order to improve the transmittance of alumina ceramics, the grain size should be controlled outside the wavelength range of incident light.

It is understood that the grain boundary is one of the important factors that destroy the optical uniformity of alumina ceramic (tube, rod) body, thus causing light scattering and reducing the transmittance of the material.And the greater the difference of material composition and refractive index, the lower the transmittance of the whole alumina ceramics.

In addition, the transmittance of alumina ceramics (tubes, rods) is also affected by the surface roughness, in addition to the fine divergence of raw materials, but also the mechanical finish of the ceramic surface.The surface of sintered and untreated alumina ceramics has a large roughness, so the ray incident on this surface will diffuse reflection, resulting in the loss of light.