Fig. 3: Thermal performance of magnetically tightened form-stable phase change materials (MTPCMs).

a DSC curves of paraffin and different volume ratio MTPCMs. b Comparison of fusion enthalpy, onset melting, and solidifying point of pristine paraffin and MTPCMs with different volume ratios. c TGA curves of paraffin and different volume ratio MTPCMs. d Temperature variations of MTPCM during the heat charging/discharging cycles and the magnified heating-freezing process in one period. e Over 1000 thermal cycles and f four selected typical heat charging/discharging cycles of MTPCM. g Thermal conductivities of pristine paraffin and MTPCMs with different volume ratios. h Schematic diagram of the directional alignment of NdFeB@Ag particles in paraffin matrix and the consequently anisotropic thermal conductivities of MTPCMs.