Optimizing Calcium Addition for Fabricating Aluminum Foams with Different Pore Sizes

抄録

This study mainly investigated the influence of Calcium (Ca) addition on the pore size of aluminum foams made by using Cu–TiH₂ composite powder as foaming agent. The Ca addition required for fabricating aluminum foams with different pore sizes was experimentally investigated. Two possible foam stabilization mechanisms were discussed and compared. For foams with pore size about 3 mm, the optimized Ca addition is 1 mass%. For foams with pore size about 2 mm, the optimized Ca addition is 3 mass%∼5 mass%. The main role of increasing melt viscosity in stabilizing foams is to prevent liquid films from thinning and rupture, rather than to prevent bubbles floating and escaping from the melt surface.

Fig. 4 Pore structure of aluminum foams fabricated by Cu–TiH₂ composite powder and different Ca addition amount: (a) 0 mass%; (b) 0.5 mass%; (c) 1 mass%; (d) 3 mass%; (e) 5 mass%; (f) 7 mass%.