Recycling aluminum offers substantial reductions in resource use, energy consumption, and greenhouse gas emissions. However, recycling post-consumer aluminum scrap typically requires high-temperature melting and the addition of 20–30 percent newly produced aluminum. The need to add newly produced primary aluminum dilutes the energy and cost benefits of recycling.

At Pacific Northwest National Laboratory, researchers have developed a method for converting post-consumer aluminum scrap directly into useful products, like automotive components and building materials, without the need for infusion of primary aluminum.

The technique relies on ShAPE™ (Shear Assisted Processing and Extrusion), PNNL’s novel, patented extrusion technique that uses rotational shear force and friction heat (rather than a preheated billet and linear force) to soften scrap and extrude it through a die. ShAPE effectively pulverizes impurities, dispersing them uniformly throughout the finished product, which lessens their impact on mechanical properties. For example, the ShAPE process has demonstrated a tolerance to excess iron, which is a common impurity in aluminum scrap. This patented technique produces a product that performs at or above industry standards for strength, ductility, and other key parameters—all without adding primary aluminum.

The result: 100 percent recycled alloys with physical properties at or above industry standards, but substantially lower feedstock costs, material waste, energy input, and carbon emissions.

This ShAPE-recycled aluminum is ideally suited for applications in building and construction, where the increased sustainability of ShAPE-recycled aluminum could be a boon for building certification programs (e.g., Leadership in Energy and Environmental Design) without sacrificing quality. ShAPE processing of recycle aluminum, which can form wires, tubes, rods, and channeled extrusions, can further benefit automotive, aerospace and defense, and consumer goods applications.