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Aluminum Integral Foams with Near‐Microcellular Structure
Author(s) -
Hartmann Johannes,
Trepper André,
Körner Carolin
Publication year - 2011
Publication title -
advanced engineering materials
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.938
H-Index - 114
eISSN - 1527-2648
pISSN - 1438-1656
DOI - 10.1002/adem.201100035
Subject(s) - materials science , blowing agent , composite material , aluminium , particle size , titanium hydride , particle size distribution , metal foam , particle (ecology) , foaming agent , decomposition , magnesium , homogeneous , chemical engineering , metallurgy , porosity , polyurethane , ecology , oceanography , titanium , engineering , biology , geology , physics , thermodynamics
In the present work the influence of the amount and size distribution of blowing agent particles (magnesium hydride, MgH 2 ) on the resulting pore structure of aluminum foams is studied. A modified die casting process called integral foam moulding (IFM) is used where aluminum melt mixed with blowing agent is injected into a mould cavity. High cooling rates at the wall of the die result in the formation of a dense shell, whereas, the decomposition of the blowing agent in the inner region leads to a cellular core. Different particle size fractions of MgH 2 are provided by sieving; the resulting pore structures of the foams are analyzed by microcomputed tomography. The results suggest that the pore size distribution represents a direct image of the size distribution of the used powder as well as of the particle density within the melt. This finding allows the production of homogeneous microcellular foams by using a high number of particles with a narrow size distribution.