Mould and method for casting quartz crucibles

Abstract

The invention discloses a mould for casting quartz crucibles, which comprises a mould main body. The mould main body comprises a mould cover, a periphery side wall and a mould core arranged in the mould cover and the periphery side wall. A crucible casting area is formed among the mould cover, the periphery side wall and the mould core, an open hole communicated with the crucible casting area is arranged on the mould cover, and a casting port communicated with the crucible casting area is arranged on the periphery side wall. The invention further discloses a method using the mould to cast crucibles, which comprises the following steps of feeding quartz slurry into a vacuum casting tank to be vacuumed, communicating the vacuum casting tank with the casting port of the mould, and connecting a funnel with the open hole on the mould cover. Thus, the quartz slurry can fill the whole crucible casting area through the casting port, and then the mould is placed horizontally to be formed. The mould and the method can reduce forming time of crucibles and improve percent of pass of the crucibles.

Description

technical field [0001] The invention relates to the technical field of quartz ceramic processing, in particular to a mold and method for casting a quartz crucible. Background technique [0002] There are two ways to prepare quartz crucible for polysilicon ingot: slip casting and gel casting. Among them, the grouting molding can be divided into two types: single-side grouting and double-side grouting. Double-sided slurry casting is adopted by most manufacturers due to its stable product quality, easy control of size and high strength. [0003] The existing double-sided pouring process mainly adopts the following two methods: (1) single-hole pouring method, that is, pouring with a hole in the middle of the upper cover of the mold, and opening a Pozi groove on the upper cover with the opening as the center to fill the corners of the crucible and exhaust. (2) Five-hole pouring method; that is, five holes are opened in the upper cover for pouring production, but this method is...

AI Technical Summary

Problems solved by technology

(2) Five-hole pouring method; it is to open five holes in the upper cover for pouring production, but this method is basically not used now due to many defects

[0005] 1. It takes a long time for pouring and molding, generally takes 40-50 hours, which affects the output and increases the cost

[0006] 2. Bubbles tend to gather at the bottom of the crucible, causing the product to be scrapped

[0007] 3. The large sprue leads to low strength at the sprue, which is prone to cracking and makes the product scrapped

[0008] 4. The amount of grinding at the Pozi groove is very large, which increases the work intensity and environmental pollution

Grinding will reduce the strength of the grinding place, and the vibration of grinding will easily cause the product to crack and make the product scrapped

[0009] 5. Due to the poor exhaust of the existing single-hole pouring, the slurry and the air contact for a long time during pouring. Since the quartz crucible slurry contains organic matter, a crust will appear after contacting the air, which will affect the strength of the crucible and easily cause internal crack defects.

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