Recent Advances in the Analysis,
Measurement, and Properties
of Composite Metal Foams
Afsaneh Rabiei, Brian Y. Lattimer, and Elias Bearinger
Abstract Composite metal foam (CMF) is a novel lightweight metal matrix
composite material with lightweight, high strength to density ratio and high energy
absorption capabilities. The material can be made out of many different metals,
alloys, and combinations, e.g. aluminum, steel, titanium, etc. For example, it can be
made 100% out of steel, but, due to its porosities, it will weigh as light as aluminum.
CMF is made of closely packed metallic hollow spheres with a metallic matrix that
fills the empty spaces in between spheres. In every combination of the spheres and
matrix materials, the final product weight will be ~30–35% of the weight of the
parent material; the rest would be the air trapped inside its porosities. In this study,
a scaled-down version of the torch fire experiments specified in 49 Code of Federal
Regulation (CFR) Part 179, Appendix B was developed to provide initial data on
evaluating the thermal protection performance of steel-steel composite metal foam
(S-S CMF) in the torch fire conditions. S-S CMF panels of 30 × 30 cm dimensions are manufactured and tested to evaluate their survivability when exposed to
a 30-minute torch fire condition of high velocity jet fire with a gas temperature of
1204°C in accordance with 49 CFR Part 179. Testing was performed to characterize
the jet burner gas temperature and velocity flow field, and a calibration fire test was
conducted using steel only as required by the test specification. The assembly was
tested in duplicate in two consecutive simulated torch fire exposures as specified in
49 CFR Part 179, Appendix B. Based on the experimental results, a 15 mm thick
steel-steel composite metal foam tested as novel insulation system met the acceptance criteria for the simulated torch fire testing and is expected to pass when tested
at a full size of 122 × 122 cm dimensions. The main factor for fire resistance and
thermal protection performance of S-S CMF is attributed to the large air content in
the material.
A. Rabiei (B)
Department of Mechanical and Aerospace Engineering, North Carolina State University, Raleigh,
NC, USA
e-mail: arabiei@ncsu.edu
B. Y. Lattimer · E. Bearinger
Department of Mechanical Engineering, Goodwin Hall, Virginia Tech, Blacksburg, VA 2406, USA
© The Minerals, Metals & Materials Society 2021
T. S. Srivatsan et al. (eds.), Metal-Matrix Composites, The Minerals, Metals
& Materials Series, https://doi.org/10.1007/978-3-030-65249-4_13
201
Measurement, and Properties
of Composite Metal Foams
Afsaneh Rabiei, Brian Y. Lattimer, and Elias Bearinger
Abstract Composite metal foam (CMF) is a novel lightweight metal matrix
composite material with lightweight, high strength to density ratio and high energy
absorption capabilities. The material can be made out of many different metals,
alloys, and combinations, e.g. aluminum, steel, titanium, etc. For example, it can be
made 100% out of steel, but, due to its porosities, it will weigh as light as aluminum.
CMF is made of closely packed metallic hollow spheres with a metallic matrix that
fills the empty spaces in between spheres. In every combination of the spheres and
matrix materials, the final product weight will be ~30–35% of the weight of the
parent material; the rest would be the air trapped inside its porosities. In this study,
a scaled-down version of the torch fire experiments specified in 49 Code of Federal
Regulation (CFR) Part 179, Appendix B was developed to provide initial data on
evaluating the thermal protection performance of steel-steel composite metal foam
(S-S CMF) in the torch fire conditions. S-S CMF panels of 30 × 30 cm dimensions are manufactured and tested to evaluate their survivability when exposed to
a 30-minute torch fire condition of high velocity jet fire with a gas temperature of
1204°C in accordance with 49 CFR Part 179. Testing was performed to characterize
the jet burner gas temperature and velocity flow field, and a calibration fire test was
conducted using steel only as required by the test specification. The assembly was
tested in duplicate in two consecutive simulated torch fire exposures as specified in
49 CFR Part 179, Appendix B. Based on the experimental results, a 15 mm thick
steel-steel composite metal foam tested as novel insulation system met the acceptance criteria for the simulated torch fire testing and is expected to pass when tested
at a full size of 122 × 122 cm dimensions. The main factor for fire resistance and
thermal protection performance of S-S CMF is attributed to the large air content in
the material.
A. Rabiei (B)
Department of Mechanical and Aerospace Engineering, North Carolina State University, Raleigh,
NC, USA
e-mail: arabiei@ncsu.edu
B. Y. Lattimer · E. Bearinger
Department of Mechanical Engineering, Goodwin Hall, Virginia Tech, Blacksburg, VA 2406, USA
© The Minerals, Metals & Materials Society 2021
T. S. Srivatsan et al. (eds.), Metal-Matrix Composites, The Minerals, Metals
& Materials Series, https://doi.org/10.1007/978-3-030-65249-4_13
201