Two-step preparation method of large Al2O3-based crystal

Abstract

The invention discloses a two-step preparation method of a large Al2O3-based crystal, comprising the following steps of: preparing Al2O3 powder and doped powder into a biscuit bar as a seed crystal bar or charge bar and enabling the top end of the seed crystal bar or the tail end of the charge bar to be on the same horizontal line with a halogen lamp; outputting the power of 2720-3060W / h by the halogen lamp in an air atmosphere, scanning and heating the biscuit bar in a reciprocating way till the biscuit bar is melted and crystallized to obtain polycrystal charge bars; with one of the polycrystal charge bars as a seed crystal and another one as a raw material bar, enabling the tail end of the raw material bar to be in contact with the top end of the seed crystal bar, wherein the contact part is on the same horizontal line with the halogen lamp; outputting the power of 3200-3400W / h by the halogen lamp in an air atmosphere; and reversely rotating the seed crystal and the raw material bar, downwards and upwards moving the raw material bar and the seed crystal bar respectively to pass through a melting zone for crystal growth. Crystals obtained with the method provided by the invention contains no impurities, has fewer small-angled crystal boundaries and shows favorable crystal quality.

Description

technical field [0001] The invention belongs to the field of crystal growth, in particular to Al 2 o 3 A two-step method for the preparation of base crystals. Background technique [0002] Corundum is widely used due to its physical properties such as high strength, high melting point, chemical inertness and various optical properties. Undoped α-Al 2 o 3 It is called white gemstone, doped with Cr 2 o 3 Al 2 o 3 The crystal is red and is usually called ruby. Corundum of other colors than ruby ​​is called (color) sapphire, such as colorless sapphire, blue sapphire, yellow sapphire, pink sapphire, green sapphire, orange sapphire, purple sapphire. Al doped with different elements 2 o 3 Crystals exhibit different colors and play an increasingly important role in the fields of industry, decoration, medical devices, optics, etc. due to their unique physical and chemical properties. As a decorative gemstone, mixed with different elements, it can be made into imitations of...

AI Technical Summary

Problems solved by technology

In contrast, other gem crystals such as Ni:Al 2 o 3 Crystal, Fe:Al 2 o 3 There are few reports on crystals, and there are few reports on its synthesis process, doping ratio, and performance applications, and its two-step growth process has not been reported.

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