Methodology of the Planned Interval Test for Metal Corrosion in Phase Change Materials

Abstract Phase Change Materials (PCMs) represent a promising technology for passive thermal management, thereby enhancing the energy efficiency of buildings. However, their widespread implementation is limited by the corrosion risk associated with metallic encapsulation materials when in contact with PCMs, which compromises their long-term stability and integrity. This contribution describes in detail and introduces the Planned Interval Test (PIT) methodology as a standardized and comprehensive approach for the systematic analysis of metal corrosion processes within dynamic PCM systems. Unlike conventional static tests, PIT enables the precise monitoring of corrosion kinetics as a function of total exposure time and the number of thermal cycles, while also identifying individual degradation phases. This information is crucial for predicting durability and designing robust encapsulation systems. The primary objective of this work is to validate a procedure for the accurate evaluation of metallic corrosion resistance, thereby supporting the development of safer and more durable PCM solutions for sustainable construction and mitigating the environmental burden resulting from premature material failure.