Abstract:
In order to fabricate Al
2O
3/Fe composite honeycombs with high-performances, 316L alloy powder, Al
2O
3 powder and binder were used as raw materials, Al
2O
3/Fe composite honeycombs were obtained by plasticizing powder extrusion and sintering at 1 200℃ for 2 h in argon atmosphere firstly. Then, the effects of adding Al
2O
3 on the structures and properties of Al
2O
3/Fe composite honeycombs were investigated by SEM, XRD and universal testing machine. The results show that metal powder particles bind together to form γ-Fe matrix network structure during sintering process, and Cr
2O
3 with polygon geometric shape is formed on the surface. Adding a small amount of Al
2O
3 can inhibit the precipitation of Cr from matrix and reduce the amount of Cr
2O
3 on the surface, which makes the sintering combination of metal powder particles more compact and the surface of structure more smooth. With Al
2O
3 content increasing, the bonding capacity for the surface of honeycomb materials with catalytic activity coating enhances, compressive strength of the composite honeycomb increases at first and then decreases, and when Al
2O
3 content is 5.0wt%, the compressive strength reaches 26 MPa. The conclusions obtained show that the mechanical properties of 5.0wt% Al
2O
3/Fe composite honeycomb are the best, and the surface paintability is preferable.