Eliminating cracks in 3D-printed metal components

Researchers at EPFL have developed a new laser 3D-printing technique to manufacture metal components with unprecedented resistance to high temperature, damage and corrosion. The method has applications in fields ranging from aerospace to power-generating turbines. 3D printing, also known as additive manufacturing, has revolutionized the way components are made, setting new standards in terms of production speed when geometric complexity is high. Manufacturers use a technique known as selective laser melting (SLM) to 3D-print metal components. With SLM, a powerful laser melts and fuses metallic powders together, gradually building a 3D component layer by layer. Any remaining powder is removed at the end of the process. But some metals and alloys cannot withstand the high temperature variations that SLM involves, causing them to crack. Researchers at EPFL's Laboratory of Thermomechanical Metallurgy (LMTM) , led by Roland Logé at the School of Engineering, have developed a new method that involves applying a second laser treatment every few layers during the building phase. This dramatically reduces cracking and produces metal components with unprecedented resistance to high temperature, damage and corrosion. The patented technique, published in Additive Manufacturing , could be used to manufacture new power-generating turbine blades or key aircraft components, for example. Shock waves - The results speak for themselves. The researchers found that the technique eliminated up to 95% of cracking normally observed in a nickel-based superalloy. They now plan to apply the method to other crack-sensitive alloys. How does it work?