Robotic additive manufacturing system featuring wire deposition by electric arc for high-value manufacturing

Increasing demand from the high-value manufacturing industries of quality, productivity, efficiency and security aligns with the ambition and driving need for novel automated robotic systems. This paper describes the motivation, design and implementation phases of the SERFOW project (Smart Enabling Robotics driving Free Form Welding). SERFOW is an automated additive manufacturing arc and wire tungsten inert gas (TIG) welding prototype to support industrial manufacturing requirements of the nuclear, aerospace and automotive industry sectors. Key innovations are found in the integration of a 3D vision system with a robotic manipulator to perform automatic free-form fusion welding for the multiple layer additive material build-up required to expand Additive Manufacturing (AM) with minimum human intervention. Welding trials were performed on samples made of Super Duplex stainless steel alloy. Metallographic observations were performed to analyze the porosity distribution and penetration on the material after welding. Also, temperature, feritescope and tensile measurements were performed. The results showed that the welding and AM process performed with the SERFOW cell are within an acceptable quality tolerance range according to the ISO 5817 and the ASME A789 welding standards.