How to make aluminum powder
If you want to make aluminum powder that is easy to ignite, (thermite) is unlikely, the particle size is too small. If you make aluminum powder for other purposes, you can use a file to frustrate it, but it is not flammable.
Production and processing methods of aluminum powder
1. Melt extrusion method:
The method is to heat and extrude the metal pigment and the remaining components of the powder coating (resin, etc.) through a screw extruder. Although metallic pigments can be mixed well with powder coatings, metallic pigments are insufficiently oriented in high-viscosity melts. In addition, in the next pulverization process, the flake structure of the pigment will inevitably be destroyed. The metal powder produced by this method has a grayish metallic effect during construction. Therefore, this method is only used for the production of hammer powder.
2. Dry mixing method:
The method is to add the metal pigment dry powder to the pulverized powder coating and mix it with a mechanical mixer. The advantage of the dry blending method is that the mixing of metallic pigments and powder coatings is not intense, thereby preventing the deformation of the flake metallic pigments, and the metallic effect will not be affected. In addition, the loose pigment/resin mixture is also very conducive to the orientation of the metallic pigments and improves the glitter effect. The disadvantage of this method is that when automatic spraying equipment is used to process the recovered powder, the separation phenomenon occurs due to the large difference in the shape, density and charge of the metal pigment and resin powder particles.
3. Bonding-Process:
In this method, the metal pigment and powder coating are dry mixed and heated at the same time, so that the temperature just exceeds the softening point of the resin. At this time, the metal pigment can be fixed and bonded to the surface of the adhesive resin powder, thereby preventing the powder from being applied. Separation of metallic pigment and resin powder during recycling after neutralization construction. It is the popular bonding method now.