Effect of diluent dosage on strength of Fe-Si-Al soft magnetic powder core.

Soft magnetic powder core generally has a low strength, which is improved by using the resin impregnation process. In this study, inactive diluent (tetrachloroethylene) and active diluent 636 (trimethylol propane triglycidyl ether) were used as the mixed diluent of the 135 epoxy resin/methyltetrahydrophthalic anhydride impregnated system, and the influence of the dosage of tetrachloroethylene on the compressive strength and the influence of impregnation process on the magnetic properties for Fe-Si-Al powder cores were studied. In addition, the formula for calculating the actual compressive strength of soft magnetic powder core was modified based on the measured compressive strength and porosity. The results show that the compressive strength of the powder core is greatly improved by the impregnation process, while the magnetic properties change slightly. When the mass ratio of resin to diluent is about 1:2, the core compressive strength reaches a maximum value of 18.43 MPa. This indicates that the diluent can be fully and evenly mixed with the epoxy resin, and can be cross-linked and cured better with the curing agent at this ratio, which improves the mechanical properties of the epoxy resin accordingly. The research results on impregnation process and formula for calculating the compressive strength of soft magnetic powder cores in this paper can provide reference for the development of mass production processes to improve the strength of soft magnetic powder cores. [ABSTRACT FROM AUTHOR]