Abstract Copper-based porous wicks were prepared by powder metallurgy using NaCl powders as pore forming agents. The effects of pore forming agent content and particle size on the porosity, pore structure, equivalent pore size, permeability and capillary pumping performance of porous wicks were investigated. The relationships among the pore structure, equivalent-pore-size and performances were discussed. The results show that, with increasing the pore forming agent content, the porosity of the porous wicks increases obviously, the number of prefabricated pores inside wicks increases significantly, which results in the connecting of prefabricated pores. With decreasing the particle size of pore forming agent, the porosity of the porous wicks reduces slightly, and the size of the prefabricated pores becomes smaller and the distribution tends to be uniform. Interstitial pores and prefabricated pores inside the wick can make up different types of pore channels. The equivalent pore size of wick is closely related to the structure and quantity of pore channels. By changing the content and particle size of the pore forming agent, different pore structure can be produced, and the equivalent pore size of the materials can be controlled. The permeability and capillary pumping performance of porous wicks is not only determined by porosity, but also by pore structure and pore size. Porous wicks with high porosity, small average equivalent pores size and concentrated pore size distribution show better capillary pumping performances.
HE Da,WANG Lin,LIU Rutie, et al. Pore characteristic and performance of sintered copper-based porous wicks[J]. Materials Science and Engineering of Powder Metallurgy, 2018, 23(4): 389-397.
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2018, Vol. 23 
