[T4] Hot Isostatic Pressing

[17C-T4-04] Capillary Performance of Bi-Porous Al Fabricated Using Space Holders with Different Sizes

*H. Shen¹, A. Suzuki¹, N. Takata¹, M. Kobashi¹ (1.Nagoya University, Japan)

Keywords:Bi-porous metal, Space holder, Capillary performance, Sintering

Capillary pressure (P_cap) and fluid permeability (K) of porous media are important for heat transfer devices including loop heat pipes. In general, smaller pore size leads to enhancing the capillary pressure but decreasing the permeability. To solve this trade-off relationship, introducing bi-modal pore size distributions is promising. In the present study, the capillary performance of bi-porous Al fabricated using NaCl space holder particles with two different sizes (approximately 400 μm and 40 μm) was evaluated and compared with that of mono-porous Al. Increasing the porosity (from 60% to 80%) of mono-porous Al with large pores around 400 μm enhanced the permeability but decreased the capillary pressure. By contrast, increasing the fraction (from 0% to 20%) of small pores (around 40 μm) in bi-porous Al with a constant fraction (60%) of the large pores led to the enhancement of both permeability and capillary pressure.