Hybrid AM/SM of Complex Bimetallic Structure

Additive manufacturing (AM), esp. laser AM, becomes a powerful tool to replace conventional methods such as casting and hot spray, due to its cost effectiveness and capability of making complex structure and composition. However, direct metal melting of high temperature materials and fabrication of corrosion resistant multi-material parts (such as 9Cr1Mo steel - 12Cr2Si steel bimetallic structures) is still a challenging field, mainly due to limited understanding of composition control, laser melting control, and melted structure formation and phase transition. Based on our patented laser AM technology and the world’s first product of fs fiber laser AM, PolarOnyx proposes, for the first time, a hybrid AM/SM system to overcome these difficulties and meet the requirement of making bimetallic structures. Significant breakthroughs were made: Achieved high density (>99%) and excellent mechanical properties for the four materials selected in this project. LBE corrosion test shows strong evidence that AM parts of 12Cr2Si / 9Cr1Mo bimetallic structures are promising for nuclear applications. PolarOnyx will prototype the hybrid AM/SM system to make nuclear quality and complex bimetallic structures. Composition optimization helps grow oxidation against corrosion. Commercial Applications and Other Benefits: In addition to the 3D AM applications (potential $44B market in 2025), material processing is another major commercial application for this project. This includes (1) Photonic device fabrications, such as waveguide, coupler, WDM, modulator, and switching; (2) all types of metal processing such as welding, cutting, annealing, and drilling; (3) semiconductor and microelectronics manufacturing such as lithography, inspection, control, defect analysis and repair, and via drilling; (4) other materials processing such as rapid prototyping, desk top manufacturing, micromachining, photofinishing, embossed holograms, and grating manufacturing.