Akademik Veri Yönetim Sistemi
Progress in Additive Manufacturing, cilt.11, sa.4, ss.1-18, 2026 (ESCI, Scopus)
This study presents a hot isostatic pressing (HIP) approach tailored for melt extrusion (MEX)-printed continuous fiberreinforced thermoplastic (CFRTP) composites, utilizing silicone molding to enable uniform pressure application. Traditional post-processing methods, such as hot pressing or powder-assisted pressing, are limited to simpler geometries. Gasbased HIP methods, which are usually effective in metal additive manufacturing, may cause internal pressure equilibration in MEX-printed polymer parts, thereby limiting pore closure. This pressure equalization prevents porosity reduction. In contrast, the flexible silicone mold allows for consistent isostatic compression, increasing the gas diffusion time preserving part geometry, reduces porosity, and enables processing of moderately complex structures. Therefore, a range of temperatures and pressures were explored to assess the influence of silicone molded HIP conditions on mechanical and thermal properties. HIP treatment effects were investigated with interlaminar shear stress (ILSS) tests for standard samples and compression tests for the complex honeycomb structures. The ILSS strength of samples was significantly influenced by the combined effects of temperature and pressure. Optimal post-processing at 75 °C and 150 bar yielded the highest ILSS (14.4 MPa), approximately 35% higher than untreated sample, revealing that controlled HIP treatment reduced delamination, indicating improved interlayer consolidation and more efficient stress transfer through the polymer matrix to the reinforcing fibers. Compression tests on CFRTP honeycomb structures revealed that silicone-assisted HIP improves stability of mechanical responses with reduction in standard deviation.