There are two components to a surface finish for any aluminum heat sink manufacturing processes. The texture of the finish and the exterior coating or protectant for the surface.
There are several different types of surface texture finishes available:
The surface of the heat sink receives a unidirectional satin finish by polishing the metal. It is easy to see the pattern of fine parallel lines in the finish.
The surface of the heat sink is polished to a bright shine.
A bead blast texture is a uniform texture with low gloss that has less reflectivity.
This texture creates a uniform, matte finish for the heat sink.
The texture of this finish is determined by the type of machine working on the metal.
Applying exterior coatings and protectants is the final step in the finishing process. Painting is the simplest exterior coating available, but here are some other coatings and protectants that can be used for aluminum heat sink designs.
Anodizing is an electrochemical process that creates a durable corrosion-resistant finish by dipping it into an acid electrolyte bath and then applying electrical current to it. This bonds to the aluminum itself, creating a surface that can’t peel or chip and can have additional processes applied to it.
This is also an electrochemical process that applies a chromate conversion coating to aluminum alloys to serve as a decorative finish or retain the electrical conductivity of the aluminum heat sink.
This process uses a dry powder that is applied using an electrostatic charge and then cured using heat. This powder is typically a thermoplastic or thermoset polymer designed to create a finish that is more durable than paint.
This chemical process does not require a current like those of electrochemical processes such as anodized and clear chromate finishes. Electroless nickel plating creates an even layer of metal over any surface. However, in order to nickel plate aluminum, you need to silver plate the part first.
Getec offers a multitude of surface finish textures and various exterior coatings and protectants. These coatings include anodize finishes such as MIL-A-8625, Type I, Type II, and Type III (Hard Anodize) and Class 1 Non-Dyed, and Class 2 Dyed (black, blue, red, and green). We also provide clear chromate, powder coating, electroless nickel plate and painted finishes for our aluminum products and heat sinks. For more information give us a call at 888-999-8499, contact us online, or send us an email at sales@getecna.com today.
