What Are Alumina Balls

Alumina balls is also called spherical alumina. It is a functional material prepared by high-temperature melt spraying method,  and mainly used in the fields of heat dissipation substrates, semiconductor packaging, ceramic filters, etc., as a thermal conductive filler for rubber, plastic, and organic silicon products. Its core advantage lies in the high content of alpha phase alumina (≥ 85%) and spherical particle morphology, with high filling capacity, high thermal conductivity, and low wear resistance.
Due to its high sphericity and controllable particle size distribution, this material can achieve high-density filling (up to 87%) in organic silicon systems, forming a low viscosity mixture. It is suitable for thermal interface materials, thermal engineering plastics, and aluminum based copper-clad laminates. The high thermal conductivity makes its filling product have better heat dissipation performance than crystalline silicon powder, while the spherical structure reduces the wear of mixing equipment. In the high-end packaging field, low alpha ray products prevent semiconductor soft failure by controlling uranium/thorium impurities (≤ 10ppb), and are applied to high computing power chips and HBM packaging. More than 50% of the global market's thermal conductive powder is spherical alumina, with a significant increase in demand for cooling in the three electric systems of new energy vehicles.
Main Features of alumina balls
1. High filling density: With its large particle diameter and broad particle size distribution, realizes high-density filling for rubber and plastic and produces compounds with low viscosity and good fluidity.
2. High thermal conductivity: High filling density enables production of compounds with higher thermal conductivity and higher heat dissipation rate compared to crystalline silica.
3. Low abrasivity: Due to its Spherical shape, less-wearing of kneading machines, forming machines and dies.
The purpose of alumina balls
(1) Heat sink, filler for heat dissipation substrate (MC substrate), heat dissipation grease, phase change film
(2) Filler for semiconductor packaging resin
(3) Organic silicon heat dissipation adhesive and filler for mixtures
(4) Ceramic filter