The rubber elastomers, widely used in aeronautical tires, are subject to experience severe dynamic cycling loading during their engineering service. In order to obtain their mechanical characteristics and potential damage mechanisms under those conditions, a dynamic loading methodology was proposed for performing Mullins effect experiments based on stress wave loading. According to the characteristics of stress wave propagation, the dimension parameters of each unit were designed and configured on the basis of Hopkinson pressure bar principle. An experimental system was then built for rubber elastomer materials, and the dynamic cyclic behavior of styrene-butadiene rubber used in tires was obtained. The analyses on the experimental original signals demonstrated that the system can obtain the increasing maximum strain during each cycle, which manifested the system can achieve the dynamic loading of Mullins effect for elastomer. Finally, the loading system specificaitons were discussed for obtaining controllable loading and unloading parameters after finely adjusting system components.

Nanorubber/epoxy composites containing 0, 2, 6 and 10 ​wt% nanorubber are subjected to uniaxial compression over a wide range of strain rate from 8 ​× ​10⁻⁴ s⁻¹ to ~2 ​× ​10⁴ s⁻¹. Unexpectedly, their strain rate sensitivity and strain hardening index increase with increasing nanorubber content. Potential mechanisms are proposed based on numerical simulations using a unit cell model. An increase in the strain rate sensitivity with increasing nanorubber content results from the fact that the nanorubber becomes less incompressible at high strain, generating a higher hydro-static pressure. Adiabatic shear localization starts to occur in the epoxy under a strain rate of 22,000 s⁻¹ when the strain exceeds 0.35. The presence of nanorubber in the epoxy reduces adiabatic shear localization by preventing it from propagating.

Metallic nanolaminated materials possess excellent mechanical properties due to their unique modulation structures and interfacial properties. However, how microdefects affect their mechanical properties is still uncertain. To evaluate the influences of void location (in the crystalline layer and the Ti/Ni interface), void diameter (d) and thickness of the intermediate layer (h) on overall tensile behaviors, various types of defective Ti/Ni nanolaminates with pre-existing void are established by the molecular dynamics method in this work. The results indicate that the strength and plastic deformation mechanisms are strongly dependent on those determinants. Yield stresses of Ti/Ni nanolaminates decrease distinctly with increasing void diameter, while peak stresses with a void in the crystalline layer decrease with increasing d/h. Different void locations lead eventually to disparate initial plastic deformation carriers around the void, and various evolutions in the microstructure of the defective Ti/Ni nanolaminates. The Ti/Ni interface plays a significant role in the tensile process. The semi-coherent interface impedes new grains and lattice dislocations from passing across the interface, while the incoherent interface facilitates dislocations generating and sliding along the interface, and absorbs the dislocations moving to the interface. The results also indicate that the strain rate significantly affects the evolution of the microstructure and the tensile properties of defective Ti/Ni nanolaminates.