The Importance of Thermal evaporation

Thermal evaporation involves heating of metals in a vacuum chamber to form desired metal layer. This process is mostly done on aluminum. Vacuum metalizing is used on EMI coating, vapor barriers, metallic finishes, reflective coating and many others places. Metalizing serves as decorative, functional or protective purposes. Resistance heating, plasma heating or electron beam are used to vaporize the coating metal. Vacuum metalizing is used to deposit aluminum on big glass mirrors of reflecting telescopes. It is important to eliminate air in the vacuum chamber to avoid discolouration when metals are heat at high temperatures. For the metal to vaporize you have to set the right temperatures. It is important to increase the average free path which metal travels.

Vaccum metalizing is ideal for decorating toys to give them metallic shine. The original material is either plastic or metal. The surface is first made smooth without mechanical buffing to give it stunning reflection. Metal has an outside part that is coated which is referred as the front face. To prevent damage of the front face, it is covered with a transparent vanish. The part that covers the back of transparent plastic is called second surface coating. The advantage with second surface coating is that the use of plastic as the exposed part. Aluminum is mostly used because of its conductivity, reflectivity and it is stable in air. Adding color to the topcoat can make different colors of ornaments from red, blue, pink and many others. However other metals such as copper, silver, gold, chromium and cadmium are used. Large surfaces can be metalized through a continuous process.

The material is mounted in vacuum chamber and unrolled for coating of one side or either side. It is important to have large volumes of aluminum for evaporation. Recently vacuum metalizing has been broadened to include thick films. These coatings are corrosion resistant. EMI shielding, RFI shielding, ESD shielding and heat shielding are achieved by vacuum metalizing. They are cost effective and environmentally friendly compared to other shielding processes. EMI/RFI shielding can be used in different industries like, telecommunication, electronics, medical, military and many other industries. Recycling of metalized plastics is possible. Oxidation of the aluminum coating takes place immediately it is exposed to air in the vacuum chamber. The electrical sensitivity won’t change after initial exposure.

To ensure plastics and jewelry last for a long time vacuum metalizing is important because of the metallic shine. You can easily get to know about vacuum metalizing service providers by just viewing sites on the internet. Ensure you look at the profile of the company. The capabilities and experience will all be in the company’s profile. The ratings and reviews will assist you to choose genuine vacuum metalizing service providers. The service provider should be flexible with the clients requirements. For any further information it is good to contact the service providers.