3D sand printing: the future of steel casting

Since the end of 2021, the voestalpine Foundry Group’s Traisen site in Lower Austria has been operating Europe’s most modern 3D sand printer for steel casting. Today, the competence center has two printers which make the process more sustainable and environmentally friendly.

For many years now, the entire Group has been looking into pioneering 3D printing with metals. This process is already being used in its own printing and research centers around the world. Additive manufacturing has long since become an established production method, particularly in the aerospace, automotive, and toolmaking industries, as well as in the field of medical technologies. At the 3D sand printing competence center in Traisen, this new technology is also used for the indirect additive manufacturing of sophisticated castings using silica sand. This serves to increase efficiency while conserving resources. 3D sand printing reduces production times and is more environmentally friendly than the method it replaces. The innovative manufacturing process is primarily used to produce castings for the energy industry and the railway sector.

Model of 3D printed sand mold

Outside meets inside

In 3D sand printing, innovative ideas are the result of thinking “Outside the Box” and implemented “Inside the (Job)Box”. A 3D printer uses CAD data to directly produce sand molds into which liquid steel is poured. The sand molds are created by the repeated application of 300-micrometer-thick layers of chemically bonded silica sand. The sand mold is created grain by grain inside the printer—the job box. By individually bonding the grains, complex molds can be produced that were not possible with traditional manufacturing methods. Thanks to this wide range of possibilities, there are (almost) no design limitations for castings. Even highly complex products can be easily realized. Large molds can be produced by printing and combining several sections.

Highest quality: The finished cast component, a gearbox housing

Shaping unlimited

Other exciting aspects of 3D sand printing include optimized sustainability and quality. The new manufacturing process eliminates the need for complicated wooden models. All in all, integrated sand recycling, lower logistics expenditures, and elimination of the wooden models make 3D sand printing much more sustainable and environmentally friendly than the process it replaces. Thanks to consistently precise production of the mold and the resulting optimum surface accuracy of the casting, 3D sand printing also offers outstanding product quality. As a result, molds can be manufactured more quickly and with more near net-shaped contours, particularly for complex castings. This significantly shortens or even eliminates final in-house processing, as well as steps such as welding and forging undertaken on the customer’s premises. Additionally, the weight of the castings is also reduced due to the lower wall thicknesses.

Tradition meets innovation

The sand printing competence center in Traisen represents a key technological advance for steel casting. The voestalpine Foundry Group will be able to offer its customers highly customized solutions of greater design complexity. The company is not only opening up new business areas for the future, it is also creating new opportunities for its employees to work in an innovative environment at our established site in Traisen.

Even more information on the 3D sand printing process can be found here: www.voestalpine.com/giesserei-gruppe