Macroscopic Conductivity of Uniaxially Compacted, Sintered Balloon Aggregates

Balloon compacts attract a great attention as a new class of lightweight materials. In the present paper, macroscopic thermal conductivity of uniaxially compacted and sintered balloons is evaluated for various compaction degrees and balloon's inner-outer diameter ratios. The compaction is modeled by making the balloons overlapped without balloon flattening, and the sintering by adding some appropriate amount of mass around overlapping necks; the whole mass is conserved in both of the modelings. The macroscopic conductivities are estimated using Kirchhoff's current law. The results are expressed in terms of the two microgeometrical parameters. It is found that the uniaxial compaction complicatedly affects the macroscopic conductivities and strength of induced anisotropy of the compacts.