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The polyurethane sponge impregnation method was used to prepare copper foam with a high porosity (85%~95%) and open-cell structure. The sintering technology was discussed in accordance with the characteristics of this method. Additionally, the composition of copper foam was analyzed and the microstructure and compressive performances of copper foam fabricated by single-impregnating and double-impregnating were measured and compared. It is indicated that the microstructure at cell wall of the copper foam can be changed and the porosity decreases slightly after treatment of double impregnating, but the compressive stress level increases from 0.5 MPa to 1 MPa which is of great importance for improving the performance of material energy absorption.