A Beginner’s Guide to Dynamic Mechanical Analysis

Dynamic Mechanical Analysis (DMA) describes a procedure in which the mechanical properties of materials are measured as a function of time, temperature, and frequency. In basic terms, dynamic mechanical analysis involves the application of a stressor on a target such as the reverberation of soundwaves acting upon a sample. The result is expressed as a ratio of stress versus strain when a tremor – or vibratory energy source – is applied to the sample. Alternative experimentation times and varied vibration intensities and frequencies are staged to note the subtle differences in the way the sample reacts.

The Purpose of Dynamic Mechanical Analysis

Dynamic mechanical analysis is employed to evaluate the various correlations between a sample’s size, structure, and its different thermodynamic or chemical qualities. Our team at RQM+ Lab Services is well-versed in content testing via dynamic mechanical analysis, providing a reliable quantitative basis for definitive conclusions about key sample properties.

Simply put, dynamic mechanical analysis allows us to connect critical sample characteristics to tangible effects incurred via thermal and/or mechanical agitation. It resolves many perceived gaps in established testing methodologies by empowering researchers to predict how certain systems will behave under given conditions. This is ideal for product profiling in quality control (QC) and production environments.

Dynamic Mechanical Analysis: Procedure

The main principle of dynamic mechanical analysis involves the use of an oscillatory energy source, which effuses equally timed vibration frequencies. Peripheral, or variable, vibrations are quenched to ensure the quality of the eventual dataset.

During dynamic mechanical analysis, exposure of the sample to the standardized frequencies coming from the vibrations creates changes in the substance’s general structure. The stiffness, softness, and damping are recorded and reported, yielding an overall ‘complex modulus’ which essentially gives a quantifiable rating of the sample’s characteristics.

Applications of Dynamic Mechanical Analysis

Applicable to a selection of surface materials and components, dynamic mechanical analysis can delve deeply into the configuration of metals, plastics, glasses, and many more. Here we present two potential use scenarios, one focused on materials and the other concerned with properties.

Testing Levels of Elasticity, Viscoelasticity or Rigidity

Dynamic mechanical analysis is routinely employed to probe specific mechanical properties to determine performance under atypical conditions, such as applied tensile strain or abrupt impacts. RQM+ Lab Services engineers can easily apply dynamic mechanical testing principles to measure the elasticity, viscoelasticity, or rigidity of various sample materials.

Investigate Thermal Transitions

Dynamic mechanical analysis can be performed in temperature sweep mode to identify glass transitions in samples at sensitivity even greater than differential scanning calorimetry.

Dynamic Mechanical Analysis with RQM+ Lab Services

This article is only intended to serve as a brief introduction to the principles and applications of dynamic mechanical analysis. If you would like to learn more, there are plenty of case studies and whitepapers available on our site. Or, for any specific questions about dynamic mechanical testing, why not contact a member of the RQM+ Lab Services team today?