Influence of Metal Supports on the Measurement of Hydrogen Permeation Properties of High-Density Polyethylene

Abstract High-density polyethylene (HDPE) is widely used in hydrogen storage and transportation, including type IV cylinders and nonmetallic pipelines. Its hydrogen permeability is a key fundamental property that determines its applicability in hydrogen-related fields. Accurate measurement of HDPE's hydrogen permeability has always been a hot topic of interest in both academia and industry. The pressure difference method is commonly applied for measuring the hydrogen permeation properties of materials, with metal supports used on the low-pressure side to prevent sample deformation. However, these supports may affect the accuracy of hydrogen permeation measurements by acting as a certain barrier to hydrogen permeation. This study investigated the impact of sintered metal supports and perforated metal supports on the hydrogen permeation properties testing of HDPE through theoretical analysis and experimental research. The results indicate that sintered metal supports have no significant effect on the hydrogen permeation testing of HDPE. In contrast, perforated metal supports alter the permeation distance and area, and the measured hydrogen permeation properties decrease as the pore area of the metal perforated support decreases. Furthermore, a correction formula for hydrogen permeation properties influenced by the perforated support was derived based on Fick's Law and Henry's Law by fitting experimental data. This study also proposes a correction method for the hydrogen permeation properties testing in HDPE based on perforated metal supports, which allows for obtaining accurate hydrogen permeation properties. This approach is crucial for the reliable assessment of HDPE materials in hydrogen storage applications.