10 Tips for Designing Medical
Components with Aluminum
To better control the increasing product develop- ment costs without sacrificing quality, medical device OEMs are turning to aluminum instead of other more costly materials to manufacture
both their new and existing components.
The following 10 tips will help manufacturers improve
their designs for aluminum medical components earlier
in the product development process, lower their overall
manufacturing costs, and speed product time to market.
1. Determine design intent. When developing new
components, designers need to fully understand the end usage and
share this information with their aluminum component manufacturer. The more a manufacturer understands about the product's end
use, the more constructive design guidance they can offer as there
are different ways to meet design challenges more effectively, efficiently, and economically, when using aluminum rather than alternative materials. For instance, rolled shapes riveted together can be
replaced by a single aluminum extruded profile, resulting in higher
strength, while eliminating joining costs.
2. Determine critical-to-function (CTF) areas.
For increased strength, lighter weight, or ease of assembly with
mating components, designers need to think through their com-
ponent’s dimensions and features to reap all the benefits of alumi-
num. Aluminum extrusions, for example, offer optimum strength-
to-weight ratios where wall thickness or profile adjustments can be
made to lower the component’s weight and still ensure its overall
3. Determine critical/non-critical tolerances.
Aluminum extrusion profiles can be made to precise tolerances or
to standard dimensional tolerances. Designers need to determine
the tolerances that are truly important for each specific part feature
or mating part(s). By collaborating with component manufacturers
to achieve design intent, applying only the truly CTF tolerances to
the print will result in less manufacturing time.
4. Understand mating components with
regard to part features and final assembly.
The versatility of aluminum extrusion makes it an ideal process for
incorporating features that make it easier to assemble components
with their mating pairs. A snap-fit hinge allows for ease of assembly and does not require special tools. Other features, such as dovetail slots, screw bosses, or internal screw chases, can significantly
minimize assembly time with mating components. Thinking through
the final assembly needs and resources in the design phase can
help designers determine features up front that can assist not only
with expediting final assembly, but also contribute to developing
ergonomic and safe assembly practices – a critical process in medical device manufacturing.
5. Understand cosmetic needs/requirements.
Designers need to determine the finished look for their aluminum
components to decide the best manufacturing method to suit their
goals. They should design with surface finish in mind. When extrud-
By Gordon Knott, Alexandria Industries
Extruded components designed with screw bosses, hinges, and many other
features, allow them to incorporate easily with mating components. The
metal alloy’s properties combined with surface finishing give designers the
wear resistance and reliability they need in a medical device component.
Alloy choice can affect the surface finish because each aluminum alloy has
different elements added and undergoes modified extrusion processes to
achieve the specific goals of the extrusion. Because the alloys have different
flow and cooling requirements, design features like wall thickness variation
and adjoining structures can affect the appearance of critical surfaces.