A Testing Method for Small Specimen Bulging Test for Evaluating the Mechanical Property of High-Density Polyethylene.

High-density polyethylene (HDPE) is a key material in modern engineering, highly valued for its versatility and wide range of applications. However, accurately assessing its mechanical performance under complex stress conditions has remained a challenge. This study developed an improved small specimen bulging test (SBT) combined with finite element simulation using ABAQUS 2017 software to more precisely evaluate the deformation resistance of HDPE. Both the experimental and simulation results showed that during the hydraulic bulging test, the maximum bulging pressure of the HDPE specimens reached approximately 22 MPa, with a maximum bulging height of about 2.6 mm. The material exhibited three distinct deformation stages: elastic deformation, plastic deformation, and large deformation near failure. Based on the experimental data and simulation results, we established a more accurate material response model for HDPE, which not only better reflects the material's behavior under actual stress conditions but also provides a reliable basis for engineering design and material selection.