Dynamic mechanical analysis (DMA) is a powerful tool for studying the viscoelastic properties and behavior of a range of materials as a function of time, temperature, and frequency. This article describes various systems and equipment used in DMA setup and discusses the processes involved in preparation of test specimen for DMA measurements. Some factors to be considered when calibrating the DMA instrument are provided, along with a description on processes for interpreting the temperature and frequency dependence of DMA curves as well as the applications of DMA.

This article presents the structural attributes and internal characteristics of spot welds as well as the commonly inspected imperfections in resistance welds. It describes the industrial requirements for weld quality. Commonly performed destructive evaluations, namely, manual testing, quasi-static mechanical tests, dynamic mechanical tests, and metallographic examination, are reviewed. The article reviews weld-quality monitoring using various process signals and provides a discussion on the on-line and off-line nondestructive evaluation methods of spot weld quality.

This article reviews the analytical techniques most commonly used in plastic component failure analysis. These include the Fourier transform infrared spectroscopy, differential scanning calorimetry, thermogravimetric analysis, thermomechanical analysis, and dynamic mechanical analysis. The descriptions of the analytical techniques are supplemented by a series of case studies that include pertinent visual examination results and the corresponding images that aid in the characterization of the failures. The article describes the methods used for determining the molecular weight of a plastic resin. It explains the use of mechanical testing in failure analysis and also describes the considerations in the selection and use of test methods.

This article focuses on various thermal analysis techniques used to verify the cure of a polymer composite. The techniques include differential scanning calorimetry (DSC), modulated DSC, thermomechanical analysis, dynamic mechanical analysis, and dielectric analysis. The article also provides an overview of the composite failure modes affected by matrix resin and testing approach.

This article discusses the deformation and viscoelastic characteristics of plastics as polymeric materials, focusing on the test methods used for the evaluation of their mechanical properties, methods available for analytically predicting the deformation response of polymers, and the effect of viscoelasticity on the test methods used. Two common ways of evaluating viscoelasticity of plastics are by means of creep experiments and dynamic mechanical experiments. Graphic or tabular analysis of test data, time-temperature superposition, and empirical correlation methods are commonly employed for analytical prediction of deformation characteristics of polymers.