Indirect heating-type synthesis assembly for high-temperature and high-pressure artificial single crystal synthesis by using cubic press

Abstract

The invention relates to an indirect heating-type synthesis assembly for single crystal synthesis by using a cubic press. The indirect heating-type synthesis assembly comprises pyrophyllite powder pressing block which is internally lined with a dolomite casing. The indirect heating-type synthesis assembly is characterized in that a cylindrical metal cup made of metal niobium, tantalum, molybdenum or tungsten is arranged in the dolomite casing, an aluminum oxide ceramic high-temperature pipe is wrapped outside the cylindrical metal cup and the aluminum oxide ceramic high-temperature pipe is made of alpha-aluminum oxide and talc through high-temperature sintering; metal conducting strips are respectively arranged on the two sides of the metal cup and are connected with the metal cup; and the two ends of the dolomite casing are respectively sealed by composite conducting plugs and the composite conducting plugs are connected with the metal conducting strips. The indirect heating-type synthesis assembly uses high-melting-point metals to make the metal cup which is also used as an electric heating element, aluminum oxide ceramic materials are additionally used for making the high-temperature protection pipe, the indirect heating-type synthesis assembly is suitable for synthesizing artificial single crystals such as diamonds by using the cubic press, the requirements of higher temperature and longer heating time are satisfied, the stability of single crystal synthesis technology and equipment is improved, the losses of anvils are reduced and favorable conditions are provided for the synthesis of gem grade diamonds.

Description

technical field [0001] The invention belongs to the technical field of diamond or other single crystal synthesis, and relates to a single crystal synthesis assembly, in particular to an indirect heating synthesis assembly (synthesis block) in the high temperature and high pressure artificial single crystal synthesis of a six-sided top press, which can be It is used for the high-pressure and high-temperature synthesis of diamond in a six-sided top press, and can also be used in the growth of cubic boron nitride, silicon carbide single crystal and gallium nitride single crystal. Background technique [0002] In the industrial production of artificial diamond, high-purity graphite is generally used as raw material, and alloy catalysts (such as alloys formed by Fe, Ni, Mn, Co, etc.) are added to convert graphite into diamond under high temperature and high pressure. Diamond synthesis usually uses a six-sided top press to provide the high temperature and high pressure required fo...

AI Technical Summary

Problems solved by technology

(2) The high-temperature insulation and thermal insulation materials made of dolomite are easy to explode due to gas discharge at high temperature

However, the thickness and size of the insulation pipe and insulation pipe used are increased, and the amount of gas generated during heating increases, which increases the risk of explosion hammer

(3) The heating element has poor stability when heated for a long time: the commonly used indirect heating heating element is cold-pressed graphite tube or electric heating alloy

(4) When heated for a long time, the temperature difference between the front and rear ends of the anvil becomes larger, and the expansion stress can easily cause the hammer to explode.

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