The structure and properties of porous copper produced by powder metallurgy using NaCl as space holder agent

Abstract

In this work, the porous copper samples were produced via the powder metallurgy using NaCl as the space holder. Cu and NaCl powders were mixed by a double-cone mixing machine and then pressed into the cylindrical pellets (12 mm in diameter) at the pressure of 100 MPa. The sintering was done in a tube furnace using hydrogen environment at 900 oC for 1h. After sintering, the samples were subjected to vibration in water for 3h to remove the NaCl particles. The results showed that the porous copper has been produced and NaCl has been completely removed after the ultrasonic process in distilled water. Using NaCl space holder, the porous structure has two types of pores: the macropore induced by the removement of NaCl and the micro-pore induced by the partial sintering of Cu powders. With increase of NaCl content from 0 to 20 wt.%, the porosity and permeability of the samples increased from 24 to 58 % and from 1.53×10-13 to 12.46×10-13 m2, respectively. However, the compressive strength of the samples has a decrease with the increase of porosity resulted from the increase of NaCl content.