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Laser cladding uses a high-energy laser beam as a heat source to rapidly melt and solidify the cladding material onto the substrate to form a high-performance coating. This technology provides an efficient and economical method to repair and remanufacture precision equipment such as engines and spacecraft. However, the inherent non-equilibrium solidification properties of laser cladding often lead to problems such as coating anisotropy, high porosity, and elemental segregation. Optimizing process parameters and heat treatment do not always eliminate these defects. Therefore, it is necessary to seek a more appropriate solution. Introducing laser remelting on the surface or between the layers of the coating to cause it to remelt and redistribute can refine the grain size, reduce defects, and improve the uniformity of the composition, thus enhancing the performance of the coating. This paper reviews and summarizes the application and development status of laser remelting technology in laser cladding and discusses it in terms of surface quality, hardness, wear resistance, and corrosion resistance of the coating. It also identifies the potential of external field-assisted laser remelting technology in further optimizing coating performance. Finally, based on the review, suggestions are provided for selecting remelting parameters. [ABSTRACT FROM AUTHOR]

Objective: To ensure the supply of prevention materials in the tertiary public hospitals in prefecturelevel cities, and to make the process of allocating prevention materials more scientific and reasonable., Methods: Open the green passage, simplify the procurement process, carry out emergency procurement of related materials, ensure timely delivery of prevention materials, distribute them at different levels, and strengthen the warehouse management of prevention materials., Results: The scheme of emergancy supplies was constantly improved, and the supply of prevention materials was completed with good quality., Conclusions: Using scientific and efficient management methods, the supply of prevention materials in medical institutions has been guaranteed, which has experience and reference significance for the prevention and control of similar public health emergencies in the future.