Liu Shenggui, Lyu Mindong, Yang Cheng, Jiang Minqiang, Wang Chao
School of Mechanics and Civil Engineering, China University of Mining and Technology, Beijing 100083, China.
The State Key Laboratory of Nonlinear Mechanics (LNM), Institute of Mechanics, Chinese Academy of Sciences, Beijing 100190, China.
Materials (Basel). 2023 Mar 20;16(6):2457. doi: 10.3390/ma16062457.
As a promising nano-porous material for energy dissipation, the viscoelastic properties of three-dimensional (3D) graphene foams (GrFs) are investigated by combining a dynamic mechanical analysis (DMA) and coarse-grained molecular dynamic (CGMD) simulations. The effects of the different factors, such as the density of the GrFs, temperature, loading frequency, oscillatory amplitude, the pre-strain on the storage and loss modulus of the GrFs as well as the micro-mechanical mechanisms are mainly focused upon. Not only the storage modulus but also the loss modulus are found to be independent of the temperature and the frequency. The storage modulus can be weakened slightly by bond-breaking with an increasing loading amplitude. Furthermore, the tensile/compressive pre-strain and density of the GrFs can be used to effectively tune the viscoelastic properties of the GrFs. These results should be helpful not only for understanding the mechanical mechanism of GrFs but also for optimal designs of advanced damping materials.
作为一种很有前景的用于能量耗散的纳米多孔材料，通过结合动态力学分析（DMA）和粗粒度分子动力学（CGMD）模拟，研究了三维（3D）石墨烯泡沫（GrF）的粘弹性特性。主要关注不同因素，如GrF的密度、温度、加载频率、振荡幅度、预应变对GrF储能模量和损耗模量的影响以及微观力学机制。发现储能模量和损耗模量均与温度和频率无关。随着加载幅度的增加，储能模量会因键的断裂而略有减弱。此外，GrF的拉伸/压缩预应变和密度可用于有效调节GrF的粘弹性特性。这些结果不仅有助于理解GrF的力学机制，还有助于先进阻尼材料的优化设计。
