Abstract: Using phenolic resin as carbon source precursor and NaCl powder along with a self-made salt ball as a pore-forming agent, high-strength multi-stage porous foam carbon was prepared by template method. The pore structure of foam carbon was regulated by the salt ball size and NaCl powder, and the effect of pore-forming agent salt ball size on the pore structure and mechanical properties of foam carbon was studied. The results showed thatwhen the volume percentage of salt ball is the same (salt ball accounted for 60 % of the volume of foam carbon embryo), with the increase of salt ball size, the uniformity of salt ball pores in multi-stage porous foam carbonis decreased, and its ligament gradually become thicker with the increase of salt ball size. There are numerous NaCl powder pores and bubble pores inside the salt ball pores and on the ligaments, which are interconnected to form an open-pore structure. The salt balls of different sizes do not significantly affect the density of the hierarchical porous carbon foam, which remain at approximately 0.2 g/cm³. However, the compressive strength decreases with the increase of salt ball size. The maximum compressive strength and specific compressive strength of the foam carbon with the particle size of 14~35 are 4.4 MPa and 22 MPa·cm³/g, respectively.

Key words: carbon foam, templating, salt sphere, mechanical