Home > News > Content

How Many Kinds Of Alumina Ceramic Forming Methods Are There

Hangzhou JWG Technology Co.Ltd | Updated: Jul 19, 2017

How many kinds of alumina ceramic forming methods are there?

There are many methods for forming alumina ceramics, such as dry pressing, grouting, extrusion, cold isostatic pressing, injection molding, hot pressing and hot isostatic pressing, etc.. In recent years, domestic and foreign have developed the press molding, direct coagulation casting molding, gel casting molding, centrifugal grouting molding and solid free molding and other forming technology. Different product shapes, sizes, complex shapes and precision products require different molding methods.

Introduce its commonly used molding:

1, dry molding: alumina ceramic dry molding technology is limited to simple shape, and the wall thickness of more than 1mm, length and diameter ratio is not greater than 4: 1 of the object. Forming methods are single axial or two-way. There are two kinds of press, hydraulic and mechanical, which can be semi-automatic or fully automatic molding. The maximum press pressure is 200Mpa. Output can reach 15~50 pieces per minute. Due to the uniform pressure of the hydraulic press stroke, the pressing parts are highly different when the powder filling is different. The size of the pressure applied to the mechanical press changes due to the amount of powder filling, which leads to the shrinkage of the size after sintering and causes the difference in the quality of the products. Therefore, the uniform distribution of powder particles during dry pressing is very important to die filling. The accuracy of the size control of the alumina ceramic parts is greatly affected by the accuracy of the filling amount. Powder particles greater than 60 mu m, between 60~200 items, can obtain the maximum free flow effect, obtain the best pressure molding effect.

2 、 grouting molding method: grouting molding is the earliest method of forming alumina ceramic. Due to the use of plaster mold, low cost and easy to shape, large size, complex shape parts. The key of the injection molding is the preparation of alumina paste. Usually with water as the flux medium, and then add glue and adhesive, fully grinding, then exhaust, and then poured into the plaster mold. The slurry is solidified in the mold due to the adsorption of moisture on the plaster mold capillary. In hollow grouting, the excess slurry should be poured out when the mold wall adsorption slurry reaches the required thickness. In order to reduce the shrinkage of the body, the high density slurry should be used as much as possible.

The alumina ceramic slurry also needs to be added with organic additives to form a double layer on the surface of the slurry, so that the slurry is stable and suspended without precipitation. In addition, it is necessary to add vinyl alcohol, methyl cellulose, ammonium alginate and other binders and polypropylene, Arabia gum powder, the purpose is to make the slurry suitable for grouting operation

Sales Manager:Jiang Zuozhong

Add:Rm 1319, Meidu Plaza, 789# Moganshan Road, Hangzhou, Zhejiang, 310011,  China

Tel: +86 571 81950201

Fax:+86 571 89923957



Hangzhou JWG Technology Co.Ltd