It is not surprising that chemical etching aluminum parts in the aerospace, automotive, and electronics industries are growing. Aluminum has many desirable properties that make it a
favorable option for components both in engine mechanical systems, electrical systems, and interior features and coverings. Although there are new types
of composites emerging that are lighter and stronger, aluminum is
less expensive because it is recyclable.
Photo etching is one of the most suitable manufacturing processes for thin
aluminum components. Aluminum is a reflective material that is
reactive to heat in the manufacturing process and therefore, makes
it less suitable for laser cutting and wire EDM processes. Although
challenging to manufacture, we have special equipment and processes
that lower the temperature in the photo etching process so the metal properties remain unchanged while maintaining
precision and low tolerances.
Metal fabrication with aluminum requires special processing to
achieve the necessary burr-free surfaces and edges that are
imperative in most components. Because aluminum is a reactive
material and oxides easily, it can create a grainy build-up of
material around the edges when exposed to light, a heated gas or an
electrical current as used in laser cutting, plasma cutting, and
wire EDM. Although these methods can cut aluminum, they are limited
in capabilities with certain design features and dimensions
especially if they are too close to an edge.
The more favorable fabrication processes for aluminum include
stamping, punching, and photochemical machining. The ductility of
aluminum allows for easy stamping and punching. However, those
processes are not suitable for parts with complex or intricate
designs and certainly not as economical for prototyping or shorter
runs because the tooling is more expensive.
Here are the benefits of acid etching aluminum compared to other types of metal fabrication processes:
- Low-cost tooling - Tooling can be produced in a matter of hours, is inexpensive and
easily modifiable. Whereas hard conventional tooling dies can cost
thousands and takes longer to make.
- Burr and Stress-Free - Other processes can incur micro-burring or extra material built
up on the edges from a reaction to heat, light or blast.
Photochemical etching can hold low dimensional tolerances without
any stress deformations.
- Unaltered Metal Properties - All the favorable aluminum properties remain intact and do not
change with the photochemical etching process.
- Complex and Intricate Designs - Aluminum part designs with small apertures such as holes, slits,
spaces, or unusual designs cost less to manufacture in large
quantities with photo etching compared to laser cutting, plasma
cutting, or wire EDM processes, and delivers better precision than
stamping.
- Quick Prototyping - The low-cost flexible tooling make it easy to expedite small
batches for prototyping.
Many industries choose aluminum over other materials due to the
attractive properties listed above. In particular, the aerospace industry requires durable, lightweight parts that will hold up in extreme
temperatures or force.
Aluminum has a higher fatigue limit than other metals. Components
in aircraft such as heat transfer plates have numerous lines that are etched simultaneously with the
etching process. In large quantities, this type of part is more
cost-effective to manufacture than other methods.
Likewise, the automotive industry can take advantage of the low-cost method when manufacturing
aluminum components such as bipolar fuel cell plates. Just like heat transfer plates, the metal etching process is more
cost-effective for these types of parts because they contain
numerous channels. The process also saves time as both sides of the
metal are etched simultaneously.
Any industry with electronic systems can count on the photo chemical etching for precision aluminum parts such as EMI/RFI shielding to resist the magnetic properties of neighboring components.
