Mechanical response of the fly ash cenospheres/polyurethane syntactic foams fabricated through infiltration process

摘要

In this paper, the low-cost syntactic foams were prepared by incorporating the fly ash cenospheres into the rigid polyurethane foams. The empirical relations were developed for predicting the porosity of the syntactic foams. Effects of the density and cenospheres size on the mechanical response of both the plain foams and aluminum foils reinforced foams were examined under quasi-static compression. The results show that, when the relative density was below 0.29, the cenospheres size marginally influenced the mechanical properties. When the relative density was above 0.29, the plain foams containing larger cenospheres exhibited better mechanical performances. For the reinforced foams, however, the mechanical properties were significantly improved by using smaller cenospheres. Moreover, the extra mechanical enhancement apart from the addition of the aluminum honeycombs was only effective for the composites containing smaller cenospheres. The reinforcing mechanisms of these composites were identified by the comparison of the mechanical properties and the analysis on their deformation behaviors. It demonstrated that the remarkable reinforcement was dominated by the failure pattern transition in the plain foams. This study may help to develop a comprehensive use of the fly ash cenospheres in civil engineering as functional materials. (C) 2019 Elsevier Ltd. All rights reserved.