Analysis of thermal expansion of solids

Thermal expansion analysis of solids allows us to measure the dimensional changes of a material when subjected to a controlled temperature variation. This property is crucial for understanding the mechanical and structural behavior of materials during thermal cycles, manufacturing processes, or use in extreme conditions. The coefficient of linear thermal expansion (CTE), often expressed in µm/m·°C, is a key indicator for anticipating the risks of deformation, cracking, or failure in demanding industrial environments. This analysis is particularly relevant to the polymer, composite, construction materials, packaging, and technical coatings sectors, where dimensional stability is a major performance factor.

Principle and operation of the method

The analysis relies on the use of a dilatometer, a device specifically designed to precisely measure the length changes of a material during temperature increases or decreases. The sample is placed in a thermally controlled chamber. An ultrasensitive displacement sensor continuously records the dimensional changes induced by these temperature fluctuations. The dilatometer then converts these changes into a coefficient of thermal expansion (CTE), allowing the material's behavior to be characterized over a defined temperature range. Beyond the CTE, the analysis can reveal other structural information: phase transitions, mechanical relaxation, irreversible shrinkage or expansion phenomena, dimensional anisotropies, or thermal compatibility between different layers of an assembly. This data is essential for optimizing formulations, designing more stable products, or avoiding thermal incompatibilities in multi-material systems.

Technical interest and industrial applications

Thermal expansion analysis is essential for any sector where dimensional variations can lead to functional defects or failures. In the polymer materials industry, it allows for adjusting the formulation of thermoplastics, evaluating the stability of composites, and verifying the dimensional stability of injection-molded parts. For composite materials, it serves as a tool for controlling the differing behaviors between organic and inorganic phases. In packaging, thermal expansion influences flatness, mechanical integrity, seal strength, and the compatibility between layers of a multilayer film. Manufacturers must ensure that their materials do not deform during the thermal variations encountered in storage, processing, or end use. In the field of coatings, controlling thermal expansion is crucial to prevent cracking, peeling, or loss of adhesion. The analysis helps anticipate incompatibilities between substrate and coating when their thermal behaviors differ. Finally, for construction materials, thermal expansion is a major design parameter to prevent accumulated stresses, cracking and structural damage in infrastructure exposed to climatic variations.

Analyzed matrices

Typical matrices studied include polymers, thermoplastics and thermosets, composite materials, elastomers, metals, ceramics, wood and wood derivatives, as well as technical papers and cardboards. Any part or material whose dimensional stability influences quality, durability, or functionality can benefit from thermal expansion analysis.

Added value YesWeLab

Thanks to a network of laboratories selected according to strict technical criteria (ISO 17025, COFRAC), YesWeLab identifies the most suitable expert laboratory for you, based on your matrix, the desired temperature range, the required analytical precision, and the applicable standards. Our scientific team has been supporting manufacturers, formulators, and engineering firms since 2020 in managing and optimizing their analytical needs. From handling your specifications to interpreting the results, we ensure rigorous monitoring via our centralized digital platform. For any specific requirement or protocol, our experts can offer you a customized analytical solution.

Related analyses in the YesWeLab catalog

To complement the analysis of thermal expansion, several associated services allow for a more complete characterization of your materials:

• ATG/TGA analysis (thermogravimetry)
• DMA analysis (dynamic mechanical analysis)
• Shore hardness measurement
• Scanning electron microscopy (SEM)
• FTIR analysis for chemical characterization