5.1 Sandwich panel cores may change planar dimensions when heated. This phenomenon can be associated with the effects of heating upon the core material itself, as well as changes in core moisture content resulting from the heating cycle. It is prudent to know if this may be problematic with regard to the intended final part dimensions.

5.2 This test method provides a standard method of characterizing the dimensional stability of sandwich core materials for design properties, material specifications, research and development applications, and quality assurance.

5.3 Factors that influence dimensional stability of sandwich core materials and shall therefore be reported include the following: core material, methods of material fabrication, core geometry, core thickness, core thickness uniformity, cell wall thickness, specimen geometry, specimen preparation, heating and cooling environments (including temperatures and humidity levels), and specimen conditioning (both prior to and after heating).

1.1 This test method covers the determination of the sandwich core dimensional stability in the two plan dimensions.

1.2 Units—The values stated in either SI units or inch-pound units are to be regarded separately as standard. The values stated in each system are not necessarily exact equivalents; therefore, to ensure conformance with the standard, each system shall be used independently of the other, and values from the two systems shall not be combined.

1.2.1 Within the text, the inch-pound units are shown in brackets.

1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.

1.4 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.