Teflon can be sprayed in the following two ways:
I. Dispersion coating.
The processing method of dispersion coating is to make the coating material evenly distributed in the solvent to form a dispersion (solid substances mixed in liquid) of a wet processing. This mixture is atomized by high-pressure air and sprayed onto the surface of the workpiece. The steps are as follows:
1. Preparation of the workpiece.
In order to obtain sufficient surface adhesion on the surface of the workpiece, it is necessary to remove all the grease from the surface to be coated. We use an organic solvent to dissolve the grease and heat it to about 400°C to evaporate it completely. In the next step, the workpiece is mechanically cleaned and roughened by sandblasting. The adhesion of the coating to the surface of the workpiece can be improved by applying a bonding aid (primer).
2. (Wet) Dispersion coating spraying.
Sprayed coating material must be uniform. The thickness of the coating depends on the coating system used; the thickness of the coating may vary from a few microns to 200 microns (0.2 mm).
3. Drying.
The wet coating is heated in an oven at a temperature below 100°C until most of the solvent has evaporated.
4, sintering.
The sintering step is to heat the workpiece to a higher temperature until an irreversible reaction occurs: the coating material melts and forms a mesh structure with the bonding aid.
Two, powder coating.
The powder coating process is a dry process where the coating material used is in the form of extremely fine solid particles. With this coating method, it avoids the use of solvents, as well as the subsequent dispersion phenomenon that occurs when the coating adheres. The process uses the appropriate method to attach the micronized coating particles to the workpiece. Subsequently, the coated micronized powder is melted in an oven. The steps are as follows:
1. Preparation of the workpiece.
In order to obtain sufficient surface adhesion on the surface layer of the workpiece, it is necessary to first remove all the grease from the surface to be coated. We use an organic solvent to dissolve the grease and heat it to about 400°C to evaporate it completely. In the next step, the workpiece is mechanically cleaned and roughened by sandblasting. The adhesion of the coating to the surface of the workpiece can be improved by applying a bonding aid (primer).
2, powder coating.
Powder particles are blown by compressed air from the trap, and on their way to the gun nozzle, there is a section of electrostatic charge. Because the particles have the same kind of charge, they repel each other on their flight path and form a uniform and consistent cloud-like spray. The workpiece to be sprayed is grounded, thus creating an electrostatically charged area between the spray gun and the workpiece. The powder particles are attracted to the workpiece and adhere to it.
3. The powder melts.
In coating technology, there is a principle difference between high temperature spraying and low temperature spraying. Such as the use of high temperature spraying, the temperature of the substrate is higher than the melting temperature of the powder material, powder particles overlay on it. In this way the micropowder is melted during the spraying process. In the case of low-temperature spraying, the temperature of the substrate is lower than the melting temperature of the powder material. The melting is then carried out in an oven.
? Expanded Information:
Teflon, the scientific name of which is Poly tetra fluoroethylene (PTFE). (Poly tetra fluoroethylene, abbreviated as PTFE), commonly known as "non-stick coating" or "easy-to-clean material".
This material is resistant to acids, alkalis, and a variety of organic solvents, and is virtually insoluble in all solvents. At the same time, PTFE is characterized by high temperature resistance, and its coefficient of friction is extremely low, so it can be used as a lubricant, but also become an ideal coating for the inner layer of easy-to-clean water pipes.
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