ISO 10545-4:2019

Overview

ISO 10545-4:2019 specifies a laboratory test method for determining the modulus of rupture and the breaking strength of ceramic tiles. It applies to all ceramic tiles and defines specimen selection, required apparatus, test procedure, acceptance criteria and reporting. This standard is part of the ISO 10545 series on ceramic tile testing and supports product qualification, quality control and comparative performance assessment.

Key topics and technical requirements

• Scope and purpose: Measurement of breaking load, breaking strength and modulus of rupture (flexural strength) for ceramic tiles.
• Specimen selection: Rules depend on the tile’s work size thickness (≥ 7.5 mm or < 7.5 mm) and maximum area. Whole tiles are preferred; large tiles may be cut to specified dimensions while keeping the tile centre in the specimen.
• Apparatus: Drying oven (105 ± 5 °C), recording pressure gauge (±2.0 %), two rubber-covered cylindrical support rods and a central loading rod (all rods covered with rubber of 50 ± 5 IRHD as per ISO 48-2). Rod diameters, rubber thickness and overlap lengths vary with tile size.
• Pre-test conditioning: Remove loose debris, dry specimens at 105 °C for at least 24 h, cool to room temperature and test within 3 hours.
• Test procedure: Place the specimen on supports with the proper surface uppermost; apply central load at a controlled rate (stress increase approximately 1 ± 0.2 N/mm per second) until breakage; record the breaking load.
• Acceptance of results: Only fractures occurring within the central third of the span are acceptable for averaging. Minimum numbers of specimens and acceptable results vary by tile area and thickness (tables in the standard).
• Calculations: Breaking strength is derived from the measured breaking load and the geometry of span and specimen width; modulus of rupture is obtained from the breaking strength and the square of the minimum thickness measured along the broken edge.
• Reporting: Test reports must reference ISO 10545-4 and include tile description, specimen count, rod dimensions, individual and mean breaking loads, breaking strengths and modulus of rupture, and a note if tests used cut tiles.

Applications and users

ISO 10545-4:2019 is used by:

• Test laboratories performing ceramic tile testing and certification
• Tile manufacturers for quality control and product development
• Architects, specifiers and contractors requiring verified flexural strength performance
• Conformity assessment bodies and regulators assessing compliance with product norms Typical uses include production batch testing, product specification validation, failure analysis and comparative performance benchmarking.

Related standards

• ISO 13006 - definitions, classification and property requirements for ceramic tiles.
• ISO 48-2 - rubber hardness measurement (used to specify rubber covering hardness for rods).
• Other parts of the ISO 10545 series covering physical and chemical properties of ceramic tiles.

Keywords: ISO 10545-4:2019, ceramic tiles, modulus of rupture, breaking strength test, ceramic tile testing, breaking load, flexural strength, test method.