Preparation of Si3N4 ceramic foams by simultaneously using egg white protein and fish collagen

Fish collagen, a kind of fibrous protein, and egg white protein were selected as foaming agent to prepare ceramic foams by protein foaming method. Ceramic foams with open porosity of 84.8–86.9%, average pore size of 216–266 μm and compressive strength of 8.7–13.7 MPa were fabricated. Studies of fish collagen addition on the influence of open porosity, pore size distribution and mechanical property of ceramic foams were investigated. In comparison with single addition of 8 wt% egg white protein, the combinational addition of 2 wt% fish collagen and 6 wt% egg white protein results in 23% increase in average pore size. In addition, the introduction of fish collagen decreases the count of small pores. Moreover, with the introduction of fish collagen, pores become regular in shape.