Multifunctional Open-Cell Copper Foam with Sphere Pores by a Modified Sintering–Dissolution Process

In this study, open-cell copper foam with completely interconnected sphere pores was prepared by a modified sintering–dissolution process using a preformed calcium chloride template skeleton as space holder. Compared with the traditional foaming process method, the open-cell copper foam prepared by this method has fewer impurities and better surface morphology. In addition, the pore distribution can be controlled by adjusting the distribution of calcium chloride particles in the skeleton. The compression performance, airflow resistance, and filtration performance of the prepared open-cell copper foam were studied. The results show that with the increase in porosity, the bearing capacity of open-cell copper foam decreases, but the width of the stress platform increases. The prepared open-cell copper foam exhibits excellent energy absorption efficiency, reaching nearly 90% at a porosity of 85%. When the porosity is 85%, the static airflow resistance of the structure is as high as 9 KPa·s·m−2. Moreover, the structure has a filtration efficiency of more than 90% as the filtration thickness exceeds 20 mm, which demonstrates the excellent filtration ability. Such open-cell copper foam shows multi-functional potential as an impact damper, sound absorber, and impurity filter.