2026-09-03 ノースカロライナ州立大学（NC State）
At 55 mph, replacing a conventional front rail with an equal-length, equal-weight composite metal foam (CMF) rail significantly reduced vehicle damage and predicted occupant head injury. By progressively absorbing crash energy between the bumper and chassis, the CMF front rail transmitted less severe impact loading to the passenger compartment. Image credit: Jie Sun.
＜関連情報＞
- https://news.ncsu.edu/2026/09/metal-foam-car-safety/
- https://www.mdpi.com/2504-477X/10/9/474
- https://www.sciencedirect.com/science/article/abs/pii/S1290072919301437
複合金属フォームを用いた車両の安全性および衝突安全性の向上 Enhancing Safety and Crashworthiness of Vehicles Using Composite Metal Foam
Aman Kaushik and Afsaneh Rabiei
Journal of Composites Science Published: 3 September 2026
DOI:https://doi.org/10.3390/jcs10090474
Abstract
Novel steel composite metal foams (CMFs) are lightweight materials made from stainless-steel hollow spheres, with entrapped air suspended within the stainless-steel matrix. In this work, the performance of CMF-core front rails, containing steel CMF within an aluminum 6061 alloy double tube, is compared against rectangular high-strength low-alloy (HSLA) 350 steel and double-octagon aluminum 6061 alloy front rails of equivalent masses and lengths. Explicit finite element models of different front rails are subjected to frontal impact with entrapped air within the CMF core modeled using the pneumatic fluid cavity technique. The inclusion of a steel CMF-core within the double-tube structure results in plateauing vehicle deceleration instead of pulsating behavior observed during the buckling of tube-only structures. CMFs containing pressurized air and core–tube interactions enhance the compressive resistance of front rails to prevent localized bucking. The CMF-core front rail increases the accident velocity required to exceed the critical accident severity and head injury criterion (HIC) by 33.73% and 39.50%, respectively, when compared to an equivalent double-octagon front rail and by 31.93% and 48.24%, respectively, when compared to an equivalent rectangular front rail. The research demonstrates that utilizing novel energy-absorbing steel CMFs within automotive front rail structures helps improve occupant safety for crashworthiness applications.
模擬プール火災試験における鋼鉄複合金属フォーム Steel-steel composite metal foam in simulated pool fire testing
A. Rabiei, K. Karimpour, D. Basu, M. Janssens
International Journal of Thermal Sciences Available online: 18 March 2020
DOI:https://doi.org/10.1016/j.ijthermalsci.2020.106336
Abstract
A comprehensive experimental and numerical simulated pool fire test is conducted on stainless steel composite metal foam (S–S CMF) panels and is reported in this study. The uncertainty assessments for the measured and calculated unexposed surface temperatures in the calibration and simulated pool fire tests on the S–S CMF specimens are also conducted and reported. This test procedure is designed to measure the thermal performance of new or untried thermal protection systems, such as S–S CMF, and to test for its survivability when exposed to a 100-min pool fire condition. The assembly was tested in triplicate in three consecutive simulated pool-fire exposures as specified in 49 CFR Part 179, Appendix B and achieved successful results. Based on the experimental and modeling results as well as the uncertainty studies, the 15.9 mm thick steel-steel composite metal foams tested as a novel insulation system met the acceptance criteria for the simulated pool fire test specified in 49 CFR 179 Appendix B by a large margin and is expected to pass with near certainty if the test were to be reproduced in a different laboratory. The main reason for successful performance of S–S CMF is attributed to the large air content in the material. The numerical studies reported in this study indicated that the low surface emissivity of the material is also contributing to the superior performance of the material to some extent. To complete the full test requirements of CFR Part 179 App. B, the material will need to be tested against the torch-fire exposure in duplicate. This research indicates that one of the potential applications of lightweight S–S CMF can be in tank cars carrying hazardous materials and replacing conventional structural steel with demonstrated benefits of excellent thermal insulation, fire resistance, low weight along with its established energy absorption capabilities.
