Thermally conductive high-voltage insulation composites with outstanding comprehensive properties through particle grading design

In order to meet the requirements of practical applications, the comprehensive performance of thermally conductive high-voltage insulating composites is worth evaluating. Guided by the particle packing theory, spherical alumina particles with different particle size distributions were compounded and filled into low-density polyethylene (LDPE), and the thermal conductivity (TC) and mechanical breakdown of different compound systems were systematically investigated. The results show that the particle grading design of small-particle filled composites has better comprehensive properties than that of single-scale or large-particle filled composites, which proves the superiority and feasibility of particle grading design. The 110-40 wt.% composite has a higher TC (0.47 W/(m K)) compared with LDPE, while maintaining excellent insulation properties (227 kV/mm) and mechanical properties (tensile strength of 10 MPa and elongation at break of 720%). Finally, studies on the application of composite materials in the field of thermal management and ice melting of steel-core aluminum insulated wires were applied, and both studies show good prospects for the applications of Al2O3/LDPE thermal conductive high-voltage insulation composites. Alumina/low-density polyethylene thermally conductive insulation composites were prepared by the gradation design of the Al2O3 filler particles, which showed very good application prospects in the fields of steel-core aluminum insulated wires for ice melting and high-voltage insulated cables. image