A novel cold-sprayed high-reflectivity Ag-Cu composite coating

To effectively reduce radiative energy loss of polysilicon chemical vapor deposition (CVD) reactors during industrial production, this study adopted cold spray (CS) technology to fabricate novel Ag-Cu composite functional coating and tested its comprehensive service performance. The microstructure characterization and mechanical property testing demonstrate that the coating possesses both excellent hardness and erosion resistance, and can meet the requirements for long-term stable service of reactor inner walls under complex working conditions. Optical performance tests show that the Ag-Cu composite coating exhibits high reflectivity in the near-infrared band, and can effectively suppress the radiative heat dissipation on the inner wall of the reactor. To further verify the actual energy-saving performance of the coating, this study conducted a comparative analysis of energy consumption of polysilicon reactors before and after coating modification based on the Polysim numerical simulation platform. The simulation results show that the energy consumption of the reference reactor with 316 L stainless steel inner wall is 111 kWh/kg. After spraying 30 % Ag-Cu composite coating on the inner wall, energy consumption decreases to 68.4 kWh/kg, representing an annual energy saving rate as high as 38.77 %. This remarkable energy consumption optimization effect confirms the enormous potential of high infrared-reflective coating for energy-saving applications in CVD reactors, and provides an effective technical solution for the green and low-cost development of polysilicon production.