Isostatic pressing is also called hydrostatic isostatic pressing.
It is a molding method that utilizes the incompressibility of liquid media and uniformly transfers pressure.
The main differences between dry pressing and isostatic pressing are as follows:
Dry pressing has only one or two pressure surfaces, while isostatic pressing uses multi-axis pressure to obtain a higher green density, and it is dense and uniform in all directions and does not become larger due to the difference in shape and thickness. The change.
The green body formed by isostatic pressing has higher strength, uniform internal structure, and no particle orientation arrangement.
Isostatic pressing uses a powder with very low water content (generally 1%-3%), and it is not necessary or rarely to use adhesives or lubricants. This is advantageous for reducing drying shrinkage and firing shrinkage.
There is no big restriction on the size of the part and the ratio between the size. Isostatic pressing can form a clay pipe with a diameter of 500mm and a length of 2.4m, and it has wide adaptability to the shape of the part.
Isostatic pressing can realize high-temperature isostatic pressing, combining forming and firing into one process.
There are two types of isostatic pressing methods
Cold isostatic pressing and hot isostatic pressing.
Cold isostatic pressing is a very important ceramic forming technology. Due to the excellent performance of parts obtained by cold isostatic pressing, it has important applications in advanced ceramic preparation and other fields. It has been successfully applied to some large-scale and complex-shaped ceramics. Products, such as thermocouple protection tubes, ceramic radomes, alumina or alumina ceramic tubes for petroleum drilling, transparent ceramic sleeves for high-pressure sodium lamps, high-voltage ceramic insulation tubes, spark plugs and carbon graphite parts are in production.