ISO 10545-8:2014

Overview

ISO 10545-8:2014 specifies a standardized test method for determining the coefficient of linear thermal expansion of ceramic tiles. The method covers measurement of dimensional change from ambient temperature up to 100 °C and defines apparatus, specimen preparation, measurement procedure and reporting requirements. The procedure is intended to support repeatable laboratory measurement for quality control and material evaluation.

Key Topics

• Principle: Determine linear thermal expansion coefficient from ambient temperature to 100 °C by measuring length change with controlled heating.
• Apparatus: Suitable thermal expansion apparatus with uniform heat distribution and a heating rate of (5 ± 1) °C/min; vernier calipers or equivalent measuring device; drying oven capable of (110 ± 5) °C; desiccator.
• Test specimens: Two specimens cut at right angles from the central portion of a tile. Ends must be ground flat and parallel. Minimum length 25 mm; cross-section side < 6 mm and area > 10 mm² where applicable. For glazed tiles, do not remove the glaze from specimen ends.
• Preparation and conditioning: Dry specimens at (110 ± 5) °C until constant mass (weight difference < 0.1% between successive 24 h weighings), then cool in a desiccator and determine initial length.
• Measurement procedure: Calibrate apparatus with a standard specimen of matching dimensions. Measure initial length to an accuracy of 0.002 × length and, during heating, to 0.01 mm. Record temperature and length at intervals not exceeding 15 °C while heating at the prescribed rate.
• Expression of results: Calculate the linear thermal expansion coefficient using the change in length between ambient and 100 °C relative to initial length and temperature rise. Report values in the form and units required by the standard.
• Test report: Must reference ISO 10545-8, describe the tile and sample preparation, and provide coefficients for both test specimens.

Applications

• Quality control: Verify batch-to-batch consistency in thermal behaviour of ceramic tiles.
• Material selection: Inform designers and specifiers about dimensional stability under moderate heating (up to 100 °C).
• Thermal compatibility: Assess compatibility of tile bodies with glazes, adhesives and substrates to reduce risk of warping, crazing or detachment.
• R&D and failure analysis: Provide reproducible data for formulation optimization and investigation of thermally related failures.

Related Standards

• ISO 10545 series (Ceramic tiles), including:
  • ISO 10545-1 Sampling and basis for acceptance
  • ISO 10545-2 Dimensions and surface quality
  • ISO 10545-9 Determination of resistance to thermal shock
  • ISO 10545-10 Determination of moisture expansion
  • Other parts covering mechanical, chemical and durability properties

This summary highlights the practical value and core requirements of ISO 10545-8:2014 for laboratories, manufacturers and specifiers working with ceramic tiles.