Polycrystalline alumina fiber chopped bulk is manufactured by the globally advanced "sol-gel" process. The structure of this material is composed of polycrystalline alumina particles, and the fiber shape presents a shape similar to bulk. Its main purpose is to be used as insulation materials and refractory insulation materials in high-temperature environments, such as in the manufacturing of high-temperature electronic devices, heat treatment furnaces, and furnaces. Due to its good chemical stability, it can also be used to manufacture other corrosion resistant parts in chemical reactors and high-temperature devices.