Abstract: Magnetic confinement fusion devices rely on superconducting magnets to generate strong magnetic fields for plasma confinement. The use of high-temperature superconductor (HTS) magnets is currently the most promising approach to achieve controllable nuclear fusion. However, the quench behavior of these magnets may induce thermal runaway and structural destruction, posing a severe threat to the safety of the device. Therefore, investigating the selection of impregnation treatment and insulation methods for HTS magnet coils is crucial for the mechanical strength, thermal stability, and quench behavior of the magnets.[Methods]　Firstly, the performance differences of various impregnation materials such as epoxy resin, paraffin wax, and ice, their effects on magnets, and corresponding optimization strategies are analyzed. Secondly, the quench characteristics of insulated winding and non-insulated winding are compared. Finally, the current research status of improved techniques, including parallel non-insulation, metallic cladding, intra-layer non-insulation, and conductive epoxy resin impregnation, is reviewed.[Conclusions]　The selection of impregnation materials and insulation methods represents a multi-objective trade-off among mechanical support, heat dissipation efficiency, and electromagnetic stability. Current research still faces challenges in terms of stability and precise control of interturn contact resistance under extreme operating conditions in fusion environments. Future studies need to advance this technology toward engineering applications through approaches such as multiphysics simulations, validation in extreme environments, and the development of new materials.

Key words: nuclear fusion, high-temperature superconductor (HTS) magnets, ice impregnation, epoxy resin, non-insulated winding, critical current, quench characteristics, multiphysics simulation