Evaporation Pellets φ2*5 Packaging Vacuum Packaging

Vacuum Evaporation coating is a Vacuum coating method in which evaporating material is heated by evaporator under Vacuum condition and sublimated, evaporating particles flow directly into the substrate and deposited on the substrate to form solid film, or heating evaporating coating material.
The physical process is from material evaporation and transport to substrate deposition and film forming. The physical process is as follows: several energy methods are used to convert the material into heat energy, and the material is heated to evaporate or sublimate to become gaseous particles (atoms, molecules or radicals) with a certain energy (0.1-0.3eV); After leaving the plating surface, the gaseous particles with the same velocity are transported to the substrate surface in a straight line with almost no collision. The gaseous particles reaching the surface of the matrix condense and nucleate into solid film. The atoms that make up the film rearrange or form chemical bonds. [1]
Evaporative thermodynamics To escape from the surface of the plated atoms or molecules in liquid or solid phase, sufficient heat energy must be obtained and sufficient thermal motion must be obtained. Only when the kinetic energy of the velocity component of its vertical surface is sufficient to overcome the energy of mutual attraction between atoms or molecules can it escape from the surface and complete evaporation or sublimation. The higher the heating temperature, the more kinetic energy the molecules have, and the more particles vaporize or sublimate. Evaporation process constantly consumes the internal energy of plating, to maintain evaporation, it is necessary to continuously supply plating heat energy. Obviously, during evaporation, the amount of vaporization of the plating (as shown by the vapor pressure above the plating) is closely related to the heating of the plating (temperature rise). Therefore, the coating growth rate is closely related to the evaporation rate of the plating material.
After the evaporation particles collide with the base material, one part is reversed and the other part is absorbed. Surface diffusion of adsorbed atoms occurs on the surface of the substrate, and two-dimensional collisions occur between the deposited atoms, forming clusters, some of which stay on the surface for a period of time and then evaporate. Clusters of atoms collide with diffusing atoms, adsorb or release single atoms, and the process repeats. When the number of atoms exceeds a certain critical point, it becomes a stable nucleus, and then continuously absorbs other and compound atoms and gradually grows up. Finally, it merges with neighboring stable nuclei and becomes a continuous film.

Advantage:

1. High specific strength (tensile strength/density)
2. Good strength
3. Better corrosion resistance performance in seawater, wet chlorine and chloride solution
4. Good low-temperature performance
5. Low elastic modulus and thermal conductivity, Nonmagnetic
6. High hardness
7. Good thermal plasticity