Pore structure and compressive property of high porosity ZL104 alloy/aluminium fiber composite foam

To obtain an open-cell aluminium foam sound-absorbing material with high sound absorption and good compressive performance, ZL104 alloy/aluminium fiber composite foams with 71% ∼ 90% porosity was prepared using the infiltration casting method. The pore structure and compressive properties of the prepared composite foams were studied, and the improved octahedral failure model of the fiber reinforcment composite foam has been established. The results show that secondary pores were distributed on the main pore wall of the composite foam to form a porous pore wall. Fibers were found in three ways: (1) embedded in pore walls, (2) penetration pores, and (3) those partially embedded in the pore wall with the remaining part extending out of the pore. The compressive properties of composite foams decreased with increasing porosity, and were related to the fiber content, diameter, and fiber-alloy interface characteristic. With the increase of the fiber content, the yield strength of the composite foam first increasing and then decreasing. The composite foam with a fiber content of 5 vol% and a fiber diameter of 0.1 mm had the best reinforcing effect when the porosity was 82%, its yield strength (4.55 MPa) was increased by 448% compared with that of the alloy foam. When the porosity was 86%, the fiber diameter was 0.1 mm, and the fiber content were 2, 5, 11, and 14 vol%, compared with the alloy foam, the yield strength of the composite foam was increased by 27.78%, 57.41%, 220.37%, and 204.7%, respectively. The fiber reinforcement effect of the composite foam was strengthened with fiber diameter decreasing. When the porosity was 89%, the fiber content was 5 vol%, the yield strength of the composite foam increased from 0.33 to 0.95 MPa with the decrease of fiber diameter from 0.20 to 0.08 mm.