论文标题
对泡沫的粘弹性响应的延迟弹性贡献
Delayed elastic contributions to the viscoelastic response of foams
论文作者
论文摘要
我们表明，泡沫的缓慢粘弹性反应是具有末端松弛的幂律流体。对蠕变和恢复测试中泡沫力学的研究表明，幂律的贡献是完全可逆的，这表明弹性响应延迟。我们演示了这种贡献如何充分说明在所有测试中观察到的非马克斯威尔特征，从而探测线性机械响应函数。相关的幂律频谱与玻璃跃迁上方机械噪声温度的系统的软玻璃流变相一致[Fielding等，J.Rheol。 44，323（2000）]，起源于超级泡沫动力学和应力扩散的组合，这在较浓的泡沫的模拟中得到了证明[Hwang等，Nat.mater。 15，1031（2016）]。
We show that the slow viscoelastic response of a foam is that of a power-law fluid with a terminal relaxation. Investigations of the foam mechanics in creep and recovery tests reveal that the power-law contribution is fully reversible, indicative of a delayed elastic response. We demonstrate how this contribution fully accounts for the non-Maxwellian features observed in all tests, probing the linear mechanical response function. The associated power-law spectrum is consistent with soft glassy rheology of systems with mechanical noise temperatures just above the glass transition [Fielding et al., J.Rheol. 44, 323(2000)] and originates from a combination of superdiffusive bubble dynamics and stress diffusion, as recently evidenced in simulations of coarsening foam [Hwang et al., Nat.Mater. 15, 1031 (2016)].
