Manufacturing process of sintering-free ceramic core

Abstract

The invention relates to a manufacturing process of a ceramic core, in particular to a manufacturing process of a sintering-free ceramic core. According to the process, the formula of the ceramic coreis adjusted, magnesium oxide with a large expansion coefficient is used as a main material, an organic adhesive and magnesium oxide are uniformly mixed, and fibers are added to enhance the strength of the mixed material. The materials are evenly mixed and then injected into a forming mold at the temperature of 80-130 DEG C, and heat preservation is conducted for 150-300 seconds so that the viscous material can be formed into a mold core. A sintering process for manufacturing a traditional mold core is omitted, so that the production efficiency is greatly improved, and the production cost is reduced.

Description

technical field [0001] The invention relates to a manufacturing process of a ceramic core, in particular to a manufacturing process of a sinter-free ceramic core. Background technique [0002] The core is a one-time mold that makes the shape of the inner cavity of the casting. In the traditional core manufacturing process, considering the rigidity of the core during the casting process, the core is sintered to ensure the strength and hardness of the core during use. [0003] The following is a traditional and mature process for making products using cores: Investment casting, also known as lost wax casting. The process is as follows: 1. Wax mold making: select suitable investment materials (such as paraffin) to make investment molds; 2. Shell making: repeat the steps of dipping refractory paint and sprinkling refractory sand on the investment mold, hardening the mold shell and drying; 3. Dewaxing: Melt the internal investment pattern to obtain the cavity; 4. Roasting: Roas...

AI Technical Summary

Problems solved by technology

[0004] The process of cleaning the core in the sixth step of the above process is extremely difficult. The main reason is that the core adopts a sintering process, which leads to a high hardness and strength of the core after sintering. Physical methods such as vibration, shot blasting, It is extremely difficult to clean by sand blasting, high-pressure water spraying, ultrasonic wave, etc., and can only be cleaned by chemical methods such as acid and alkali corrosion

While using chemical methods to clean the core, it will also corrode the casting itself, causing damage to the casting, and even consider the issue of environmental pollution.

[0005] The sintered core will cause follow-up problems in the casting process, mainly reflected in the insufficient yield of the sintered core, which is prone to cracks when the metal liquid solidifies, resulting in flaws in the finished casting and rough inner surfaces, etc. question

[0006] Affected by inherent thinking, since the core needs to be sintered, the core raw materials used in the prior art are basically silica (quartz), magnesia plus sintering agent (mineralizer) or alumina as the base material. Cores (these cores are collectively referred to as sintered ceramic cores), the cores sintered out of these raw materials will repeatedly produce the problems of difficult core cleaning and casting defects

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