Challenges in Mechanics of Time-Dependent Materials, Volume 2 of the Proceedings of the 2019 SEM Annual Conference& Exposition on Experimental and Applied Mechanics, the second volume of six from the Conference, brings together contributions to this important area of research and engineering.  The collection presents early findings and case studies on fundamental and applied aspects of Experimental Mechanics, including papers in the following general technical research areas:  Characterization Across Length ScalesExtreme Conditions & Environmental EffectsSoft Materials and BiomaterialsDamage, Fatigue and FractureStructure, Function and PerformanceRate Effects in ElastomersViscoelasticity & ViscoplasticityResearch in Progress In-situ Techniques and Microscale Effects on Mechanical BehaviorFracture and Fatigue in Brittle Materials Novel Experimental MethodsFatigue and Fracture in Extreme EnvironmentsIntegration of Models and Experiments Failure in Elastomers and GelsRate Effects in ElastomersMicroscale and Microstructural Effects on Mechanical Behavior Mechanics of Energy MaterialsAdditive Manufacturing: Fatigue and FractureMechanics of Composite MaterialsInterfacial and Mixed-Mode FractureVibration Effects and High Cycle Fatigue