Rapid Process Shapes Aluminum

One key to making inexpensive metal parts is being able to quickly manufacture intricate shapes. Rapid prototyping processes are routinely used for plastics and some metals, but aluminum has proved elusive.

Aluminum is tricky because it conducts heat very quickly and is also highly reflective, making it difficult to turn powdered aluminum to liquid with lasers.

Researchers from the University of Queensland in Australia have come up with a rapid manufacturing process for aluminum that infiltrates an aluminum alloy powder with a liquid aluminum alloy.

The process paves the way for fast, inexpensive manufacturing of aluminum prototypes and parts. Objects made using the process have the same properties as ordinary cast aluminum, but can contain more complex shapes and smaller features, according to the researchers.

The process is similar to the rapid prototyping method used for steel, which infiltrates steel power with bronze. The process also adapts rapid prototyping methods for manufacturing parts from computer-generated designs.

The trick to adapting these methods to aluminum was first forming an object using a combination of aluminum powder and resin. At the start of the infiltration process the heat burns off the resin but hardens the powder in time to hold the object's shape.

The system could be ready for commercial use in one or two years, according to the researchers. The work appeared in the August 29 issue of Science.