Effect of SWCNTs content and relative density on the energy absorption capabilities of closed-cell Al-cenosphere-SWCNTs hybrid foam

• Published in: Composites. Part B, Engineering Engineering, 2019-11, Vol.176, p.107304, Article 107304
• Main Authors: Muchhala, Dilip, Yadav, B.N., Kumar, Rajeev, Mondal, D.P., Venkat, A.N.Ch
• Format: Article
• Language: English
• Subjects: Elastic modulus; Empirical relations; Energy absorption; Hybrid foams; SWCNTs
• ISSN: 1359-8368; 1879-1069
• DOI: 10.1016/j.compositesb.2019.107304

Al-Cenosphere-SWCNTs closed cell hybrid foams (HFs) of varying relative densities (ρrd) were synthesized through stir casting technique using TiH2 (0.6 wt % of alloy) as a foaming agent, processed SWCNTs (0, 0.1, 0.2, 0.3 and 0.4 wt %) and cenosphere (4.25 wt % or 15 vol %) as thickening agent. Cenosphere particles provided micro-porosity within the cell wall and its shells act as reinforcement. It was noted that the addition of SWCNTs and Cenosphere improved the mechanical properties such as elastic modulus (Ef), plastic collapse stress (σpc), plateau stress (σpl) and, energy absorption capabilities (Eab) of HFs. In HFs these properties increases with increase in SWCNTs up to 0.3 wt % and a further increase in SWCNTs content leads to the reduction of these properties of HFs. It is interestingly observed that the densification strain (εD) for a constant ρrd is almost invariant to the SWCNTs content. The mechanical properties of the AFs and HFs foamsareempirically simulated and also compared with standard existing models for the different SWCNTs contents and ρrd. The deformation mechanism has been examined during compression test. In the present investigation, a closed-cell Al-Cenosphere-SWCNTs hybrid foam has been developed through stir casting technique using aluminum (LM13) as a metrix, TiH2 as a foaming agent, SWCNTs, and cenosphere as a reinforcement as well as thickening agent. The results shows that cenosphere and SWCNTs content strongly influenced the deformation responses of HFs foam. [Display omitted] •Al-Cenosphere–SWCNTs, HFs of varying ρrdwere synthesized through stir casting technique with varying foaming temperature.•Cenosphere particles work as a thickening or stabilizing agent and also provided the microporosities within the cell wall.•Mechanical properties such as σpcand Eabare largely influences by the SWCNTs content andρrd.•The compressive deformation responses of AFs and HFs are correlated with existing empirical models.