Compression-Compression Fatigue Behavior of Open-Cell Foam Copper

Uniaxial quasi-static compression and compression-compression fatigue tests were performed on open-cell foam copper with the same pore size. The compression characteristics and fatigue behavior of open-cell foam copper were analyzed, and the fatigue failure mode and failure mechanism were discussed. The results show that the compressive stress-strain curve of open-cell foam copper consisted of elastic deformation stage, platform stress stage, and compaction stage. During compression-compression fatigue process, the open-cell foam copper mainly experienced fatigue damage accumulation zone, strain surge zone, and continuous failure zone. The lower the stress level, the longer the life of open-cell foam copper. Under the action of shearing force, the middle part of the open-cell foam copper formed an extruded zone with a certain angle to the horizontal direction. As the accumulated strain increasing, the pore structure in the extruded zone continued to be destroyed and formed an almost horizontal crush zone. The fatigue failure mechanism of open-cell foam copper was the peeling, necking, fracture of pore edges, and cracking of pore junction.