In our collective move towards energy-efficient transport, there is increasing pressure to reduce the weight of vehicles and aircraft. Composites, with their exceptional strength-to-weight ratio, corrosion resistance, and stiffness are extensively used within the automotive and aerospace industries for weight reduction.
Despite the prevalence of carbon and glass fiber composites, research in the composite material development field continues at a rapid pace. New materials like graphene, carbon nanotubes, and high-performance polymers are being developed within research establishments worldwide. As the pressure to reduce weight even further intensifies, the race is on to develop the next generation of advanced composite materials.
Core to the development of new high-performance composites is ensuring their physical properties hold up to demanding applications. With light-weight composites in use in aircraft fuselages and body panels, in-depth evaluation of stiffness, strength, and damping properties are required. Dynamic mechanical analysis (DMA) is extremely useful in analyzing the viscoelastic properties of materials and is especially good at detecting the glass transition temperature with very high accuracy.
DMA: A quick overview
In simple terms, a varying (dynamic) force is applied to a sample, and any associated deformation of the sample is detected. The relation between the applied force (which is sinusoidal) and the deformation gives you a lot of useful information – especially if the temperature is also varied. For example, elasticity and viscosity can be calculated from the applied stress and strain plotted as a function of temperature and / or time.
Why is DMA so useful for composite development?
The main use of DMA is to measure the viscoelastic properties of materials, with a focus on highly accurate glass transition temperature determination. Essentially, DMA gives researchers a tool to quickly determine the very properties they are trying to establish, or avoid, in novel composite development. For automotive, aircraft, and electronics applications, DMA analysis can be used to assess changes in mechanical behavior, such as stiffness or damping, due to variations in temperature, stress, or frequency. This delivers essential information for developing composites that can withstand the environmental conditions of both aerospace and electronics applications.
DMA also plays a crucial role in determining the curing levels of carbon fiber composites. Often, a full cure is not desired, and DMA can precisely identify the optimal level of curing needed to achieve the desired properties. Additionally, it can assess the curing status of the prepreg before use.
DMA is only one of a range of thermal analysis techniques available to support composite material research.
Thermo mechanical analysis (TMA) measures change in sample dimensions as a function of time or temperature. It’s used for evaluating expansion or shrinkage of samples across a wide temperature range and assesses thermal expansion in high precision and glass transition temperature.
Simultaneous thermogravimetric analysis (STA) measures DSC and TGA simultaneously in a single unit. STA is used to evaluate thermal resistance, decomposition temperature, quantitative analysis of components by TGA data, and heat capacity Cp testing with DSC.
Differential scanning calorimetry (DSC) is used to measure heat flow for material characterization by providing thermal properties such as melting point, glass transition, and crystallization.
NEXTA DMA200 is a dynamic mechanical analyzer for advanced materials development and product quality control.
As the most recent addition to Hitachi High-Tech's high-specification thermal analysis range, the DMA200 offers increased maximum force capability and built-in efficiency with straightforward troubleshooting, seamless data exchange, and easy measuring head interchangeability. Real View® enables valuable real-time furnace observations, ‘Guidance Mode’ aids DMA novices and electrical gas cooling as an alternative to liquid nitrogen for sub-zero measurements.
The upgraded 20N maximum force capability of the DMA200 is a twofold increase compared to our previous model. This allows customers to exert higher levels of stress on their samples, making it ideal for characterizing materials that require significant force for deformation.
This expanded functionality is particularly beneficial for customers dealing with stiff samples, such as carbon fiber composites, enabling them to achieve precise and reliable material characterizations. From aerospace applications to cutting-edge automotive technologies, the DMA200's enhanced force capability enables deeper exploration of the mechanical behavior of a wide range of materials.
The advancements in composite material development are crucial for the future of energy-efficient transport. By leveraging advanced tools like the NEXTA DMA, researchers and manufacturers can ensure that new composites meet the stringent requirements of high-performance applications. This not only supports the development of lighter, stronger, and more durable materials but also accelerates the transition to sustainable transportation solutions.
Find out more about the DMA200 here: https://hha.hitachi-hightech.com/en/product-range/products/thermal-analyzer-series/dynamic-mechanical-analyzer-dma200
