The principle of dry powder pressing molds, which means that high-purity powders are inert materials, will be shaped by traditional processes. The first step is to change the surface properties of the powder by adding a certain amount of surfactant, including changing the surface adsorption properties of the particles, and changing the shape of the powder particles, thereby reducing the agglomeration effect of the ultrafine powder and making it evenly distributed.
Dry powder pressing mold processing, but also pay attention to adding lubricants to reduce the friction between the particles and the particles and the model surface; add adhesives to enhance the bond strength of the powder. After the powder is subjected to the above pretreatment, the powder is loaded into a mold, and the powder is compacted into a compact body by a press or a dedicated dry press molding machine with a certain pressure and pressing method.
Dry powder pressing dies for dry powder processing will in fact include one-way pressurization, two-way pressurization (two-way simultaneous pressurization, two-way pressurization separately), and four-way pressurization. Improved dry-press molding includes vibratory pressing and magnetic field pressing (applicable to metal powders).
When the dry powder pressing mold is processed, there are some factors that directly affect the quality of the processing, such as the nature of the powder, including particle size, particle size distribution, shape, and moisture content. Afterwards, it also includes the characteristics of additives and their effects. The good additives can improve the powder's fluidity, packing density and uniformity of distribution, thereby improving the molding properties of the body. The pressure during the pressing process, the pressure mode and the pressure rate, generally speaking, the greater the pressure, the greater the density of the body, and the two-way pressure performance is better than the one-way pressure, and at the same time, the pressure speed, pressure holding time, and pressure relief speed And so on have a greater impact on the performance of the body.
The reason why dry powder pressing dies are widely used is because of the relatively high production efficiency, low labor, low reject rate, short production cycle, high density and high strength of products, and suitable for large-volume industrial production; more about dry powder pressing dies Outstanding applications Ceramics production in the dry-press method of production of products mainly include ceramic tile, wear-resistant ceramic lining tiles, sealing rings and so on.