Method for producing ceramic die core

Abstract

The invention provides a method for producing a ceramic die core. The method comprises the following steps of (1) producing a ceramic die core blank; (2) pre-treating a filler for the shaping of the ceramic die core, specifically adding the filler to be treated into a nonmetal material hopper with de-ionized water, continuously stirring slurry obtained by mixing powder and de-ionized water, continuously dropwise adding analytically pure hydrochloric acid to adjust the pH value of the slurry to 4 to 6, stopping adding analytically pure hydrochloric acid when the pH value is changed by less than or equal to 0.2 within 5 minutes, continuing stirring the slurry for 10 to 60 minutes, standing and settling the slurry for 4 to 12 hours, pouring an upper-layer solution, washing settled powder for 1 to 3 times by using de-ionized water until the pH value of an obtained solution is 6 to 8, drying the powder finally sinking to the bottom at 100 to 140 DEG C, calcining the powder for 4 to 6 hours at 1200 to 1500 DEG C, and crushing and sieving the powder; (3) performing shaping calcination; (4) performing reinforcement reconditioning. The method is simple, economical and low in time consumption, manpower is saved, energy consumption is eliminated, the production efficiency of the ceramic die core is greatly improved, and the quality of the ceramic die core is improved.

Description

technical field

[0001] The invention relates to a manufacturing method of a ceramic core, in particular, simple pretreatment is performed on fillers for ceramic core molding, which saves multiple steps of firing fillers with cores, and the surface of the ceramic core baked by the processed fillers is smooth and free of Bumps, peeling, cracks and other defects. Background technique

[0002] The ceramic core is a key transition piece for the formation of complex inner cavities during precision casting of gas turbine blades, aeroengine turbine blades and other precision metal parts, which determines the shape and accuracy of the inner cavity of the casting. In order to meet the requirements of precision casting, ceramic cores generally need to meet the following conditions: high refractoriness; Low thermal expansion rate, stable size; Sufficient high temperature strength and low temperature strength; Good chemical stability; Easy to remove. For this reason, the produ...

Examples

Embodiment 1

[0033] The following is the first method of treating fillers for ceramic core molding:

[0034] 1. Add 40 kg of high-temperature alumina into a non-metallic bucket filled with 3 times the volume of deionized water while stirring, and keep stirring for 5 minutes to prevent the powder from sinking to the bottom.

[0035] 2. While stirring, continuously drop concentrated hydrochloric acid to adjust the pH of the slurry to 6.0. The pH should change to ≤0.2 within 5 minutes. Continue stirring for 10 minutes and let stand for 4 hours.

[0036] 3. Pour off the upper layer solution, add an equal amount of deionized water, mix well, stir for 10 minutes, let it stand for 4 hours, measure the pH of the upper layer solution, if the pH is between 6-8, pour the upper layer solution, and the remaining powder is processed in the next step , otherwise repeat this step until the pH of the upper layer solution reaches 6-8.

[0037] 4. Put the powder into an oven, dry it at 100°C, then roast it ...

Embodiment 2

[0039] The following is the second method of processing fillers for ceramic core molding:

[0040] 1. Add 40 kg of high-temperature alumina into a non-metallic bucket filled with 3 times the volume of deionized water under stirring, and keep stirring for 10 minutes to prevent the powder from sinking to the bottom.

[0041] 2. While stirring, continuously drop concentrated hydrochloric acid to adjust the pH of the slurry to 5.0. The pH should change to ≤0.2 within 5 minutes. Continue stirring for 30 minutes and let stand for 8 hours.

[0042] 3. Pour off the upper layer solution, add an equal amount of deionized water, mix well, stir for 30 minutes, let it stand for 8 hours, measure the pH of the upper layer solution, if the pH is between 6-8, pour the upper layer solution, and the remaining powder is processed in the next step , otherwise repeat this step until the pH of the upper layer solution reaches 6-8.

[0043] 4. Put the powder into an oven, dry it at 120°C, then roast...

Embodiment 3

[0045] The following is the third method of processing fillers for ceramic core molding:

[0046] 1. Add 40 kg of high-temperature alumina into a non-metallic bucket filled with 3 times the volume of deionized water under stirring, and keep stirring for 20 minutes to prevent the powder from sinking to the bottom.

[0047] 2. While stirring, continuously drop concentrated hydrochloric acid to adjust the pH of the slurry to 4.0. The pH should change to ≤0.2 within 5 minutes. Continue stirring for 60 minutes and let it stand for 12 hours.

[0048] 3. Pour off the upper layer solution, add the same amount of deionized water, mix well, stir for 60 minutes, let it stand for 12 hours, measure the pH of the upper layer solution, if the pH is between 6-8, pour the upper layer solution, and the remaining powder is processed in the next step , otherwise repeat this step until the pH of the upper layer solution reaches 6-8.

[0049] 4. Put the powder into an oven, dry it at 140°C, then roa...

technical field

[0001] The invention relates to a manufacturing method of a ceramic core, in particular, simple pretreatment is performed on fillers for ceramic core molding, which saves multiple steps of firing fillers with cores, and the surface of the ceramic core baked by the processed fillers is smooth and free of Bumps, peeling, cracks and other defects. Background technique

[0002] The ceramic core is a key transition piece for the formation of complex inner cavities during precision casting of gas turbine blades, aeroengine turbine blades and other precision metal parts, which determines the shape and accuracy of the inner cavity of the casting. In order to meet the requirements of precision casting, ceramic cores generally need to meet the following conditions: high refractoriness; Low thermal expansion rate, stable size; Sufficient high temperature strength and low temperature strength; Good chemical stability; Easy to remove. For this reason, the produ...

Examples

Embodiment 1

[0033] The following is the first method of treating fillers for ceramic core molding:

[0034] 1. Add 40 kg of high-temperature alumina into a non-metallic bucket filled with 3 times the volume of deionized water while stirring, and keep stirring for 5 minutes to prevent the powder from sinking to the bottom.

[0035] 2. While stirring, continuously drop concentrated hydrochloric acid to adjust the pH of the slurry to 6.0. The pH should change to ≤0.2 within 5 minutes. Continue stirring for 10 minutes and let stand for 4 hours.

[0036] 3. Pour off the upper layer solution, add an equal amount of deionized water, mix well, stir for 10 minutes, let it stand for 4 hours, measure the pH of the upper layer solution, if the pH is between 6-8, pour the upper layer solution, and the remaining powder is processed in the next step , otherwise repeat this step until the pH of the upper layer solution reaches 6-8.

[0037] 4. Put the powder into an oven, dry it at 100°C, then roast it ...

Embodiment 2

[0039] The following is the second method of processing fillers for ceramic core molding:

[0040] 1. Add 40 kg of high-temperature alumina into a non-metallic bucket filled with 3 times the volume of deionized water under stirring, and keep stirring for 10 minutes to prevent the powder from sinking to the bottom.

[0041] 2. While stirring, continuously drop concentrated hydrochloric acid to adjust the pH of the slurry to 5.0. The pH should change to ≤0.2 within 5 minutes. Continue stirring for 30 minutes and let stand for 8 hours.

[0042] 3. Pour off the upper layer solution, add an equal amount of deionized water, mix well, stir for 30 minutes, let it stand for 8 hours, measure the pH of the upper layer solution, if the pH is between 6-8, pour the upper layer solution, and the remaining powder is processed in the next step , otherwise repeat this step until the pH of the upper layer solution reaches 6-8.

[0043] 4. Put the powder into an oven, dry it at 120°C, then roast...

Embodiment 3

[0045] The following is the third method of processing fillers for ceramic core molding:

[0046] 1. Add 40 kg of high-temperature alumina into a non-metallic bucket filled with 3 times the volume of deionized water under stirring, and keep stirring for 20 minutes to prevent the powder from sinking to the bottom.

[0047] 2. While stirring, continuously drop concentrated hydrochloric acid to adjust the pH of the slurry to 4.0. The pH should change to ≤0.2 within 5 minutes. Continue stirring for 60 minutes and let it stand for 12 hours.

[0048] 3. Pour off the upper layer solution, add the same amount of deionized water, mix well, stir for 60 minutes, let it stand for 12 hours, measure the pH of the upper layer solution, if the pH is between 6-8, pour the upper layer solution, and the remaining powder is processed in the next step , otherwise repeat this step until the pH of the upper layer solution reaches 6-8.

[0049] 4. Put the powder into an oven, dry it at 140°C, then roa...