Strength Assessment of PET Fiber-Reinforced Composites for Prosthetic Sockets.pptx

Analysis on PET fiber-reinforced composite for prosthetic socket compare to conventional fibers.

1. Strength Assessment of PET Fiber-Reinforced Composites for Prosthetic Sockets Y R Nagarajan, F Farukh, V V Silberschmidt, K Kandan, R Rathore, A K Singh and P Mukul (De Monfort University, Loughborough University, United Kingdom) ( Malaviya National Institute of Technology, National Institute of Technology, Jaipur, India) M aterials 2023, 16, 4606. https://doi.org/10.3390/ma1613406 Presentasi oleh: Mulyadi, ST, MT Sebagai Tugas Mata Kuliah Kolokium Program Doktor Teknik Mesin Universitas Andalas Padang 17 September 2025 Material Testing Engineering Analysis Prosthetics Research

2. Background and Challenges Importance of Prosthetic Sockets Connection: Critical link between residual limb and prosthetic device Comfort: Proper fit and comfort ensure effective prosthetic function Load-bearing: Lower limb sockets various loads during walking Global Context WHO estimates 35-40 million people need prosthetics globally Resource-limited nations (LRNs): Face significant barriers to access Primary reason for abandonment: High repair and replacement costs Current Challenges in Resource-Limited Nations High Cost Advanced materials like glass fiber, carbon fiber, and Kevlar fiber-reinforced resins are prohibitively expensive (custom socket can cost $6,000-20,000 in first five years after amputation) Material Limitations Thermoplastics (HDPE, PP) lack sufficient strength and stiffness to withstand axial and shear stresses from body weight and gait Natural Fiber Limitations Natural fibers require bonding with epoxy or polyester resin; lack sufficient stiffness and strength to support limbs during prosthetic use 3D Printing Limitations Despite progress in automated design, strength remains a significant limitation for clinical application, and high cost prevents large-scale production Strength Assessment of PET Fiber-Reinforced Composites for Prosthetic Sockets 2025-09-17

3. Material Selection and Properties Material Microstructure Comparison Cross-section micrographs of (a) GFRP, (b) PETW, and (c) PETK composites Material Property Comparison Material Young's Modulus (GPa) Yield Strength (MPa) Failure Stress (MPa) Failure Strain (%) GFRP 12.1 ± 1.49 - 178.77 ± 2.81 2.75 ± 0.05 PETW 3.60 ± 0.17 34.27 ± 0.52 90 ± 1.88 18.85 ± 0.28 PETK 3.16 ± 0.14 20.05 ± 0.35 41.18 ± 0.92 18.5 ± 0.17 HDPE 0.86 ± 0.07 16.01 ± 0.17 17.17 ± 0.22 49 ± 0.96 PP 0.3 ± 0.04 6.24 ± 0.49 7.4 ± 0.48 >50% Material Benefits Recycled PET Fiber (rPET) Advantages Widely available from discarded plastic bottles and food packaging Significantly cheaper than synthetic fibers in LRNs Easier to access in resource-limited settings Manufacturing Benefits VARTM process creates strong bonds between fiber layers Minimal voids in the composite structure Performance Benefits PETW and PETK show elastic-plastic response vs. elastic-brittle of GFRP PETW and PETK have comparable properties with lower cost Key Insight PET fiber-reinforced composites offer a sustainable, accessible alternative to traditional materials for prosthetic sockets in resource-limited nations. Strength Assessment of PET Fiber-Reinforced Composites for Prosthetic Sockets 2025-09-17

4. Manufacturing Methodology VARTM Technique for Composites 1 Stack 6 layers of fabric 2 Clean with acetone 3 Apply release agent 4 Place vacuum bag 5 Apply 1 atm vacuum 6 Inject polyester resin Single-piece Plates Manufacturing HDPE 1 Cut HDPE pipe in half 2 Heat at 200°C for 40 min 3 Press to 4mm thickness PP 1 Preheat 6mm PP plate at 160°C for 40 min 2 Press to 4mm thickness Test Socket Manufacturing PETK Socket 1 3D print PoP mold 2 Wrap PET yarn sock 3 Apply 8 layers of PETK 4 Vacuum assist resin injection Thermoplastic Sockets 1 Preheat plate at 160-200°C 2 Place on PoP mold 3 Apply vacuum at 1 atm 4 Allow to cool VAT process and trimmed test sockets (a) PP socket, (b) HDPE socket Material Comparison GFRP: 215 g/m² PETW: 440 g/m² PETK: 220 tex HDPE: 200 mm dia Matrix Material: IP2 polyester resin Socket Design: Standard geometry with pyramid connector Strength Assessment of PET Fiber-Reinforced Composites for Prosthetic Sockets 2025-09-17

5. Tensile Testing Results Response Characteristics GFRP Composite Elastic-brittle response Highest strength and stiffness PET Composites Elastic-plastic response Better ductility than thermoplastics PP & HDPE Elastic-plastic response Lower strength and stiffness Mechanical Property Comparison * Error bars represent standard deviations from multiple measurements Key Findings Strength Comparison PETW and PETK show superior strength compared to thermoplastics PETW failure strength (90 MPa) is twice that of PETK (41 MPa) PETW and PETK have higher strength than GFRP Stiffness Analysis Young's modulus comparison: GFRP shows highest stiffness (12.1 GPa) PETW (3.60 GPa) and PETK (3.16 GPa) show similar values Thermoplastics have very low stiffness (0.3-0.86 GPa) Deformation Characteristics Failure strain comparison: PETK shows higher ductility (18.5%) than PETW (18.85%) Thermoplastics show very high strain at failure (>50%) Strength Assessment of PET Fiber-Reinforced Composites for Prosthetic Sockets 2025-09-17

6. Socket Performance Assessment Stiffness Comparison (N/mm) Socket Weight (g) Performance Metrics Socket Stiffness Weight Specific Stiffness GFRP 319 ± 3 595 0.5361 PETW 233 ± 2 297 0.7845 PETK 159 ± 5 245 0.6490 HDPE 140 ± 2 283 0.4947 PP 135 ± 1 261 0.5172 Key Findings All sockets could withstand 125kg target load without failure PETW showed best resistance to deformation (5.37mm at 1250N) PETK demonstrated good resistance (7.16mm at 1250N) Single-piece PP and HDPE showed excessive deformation (>9mm) PETW and PETK showed higher specific stiffness compared to other materials PETW and PETK demonstrated superior weight reduction (297g and 245g vs 595g) Strength Assessment of PET Fiber-Reinforced Composites for Prosthetic Sockets 2025-09-17

7. Comparative Analysis Material Comparison Metrics Key Performance Insights: PETW and PETK show higher specific stiffness than GFRP, HDPE, and PP PETW and PETK have comparable weight to HDPE sockets PETW and PETK demonstrate better resistance to deformation under load PETW and PETK offer lower cost than GFRP and comparable cost to HDPE Comparative Benefits Specific Stiffness PETW and PETK (0.6490-0.7845 N/mm·g) demonstrate superior specific stiffness compared to GFRP (0.5361 N/mm·g), HDPE (0.4947 N/mm·g), and PP (0.5172 N/mm·g). Weight & Cost PETK (245 g) and PETW (297 g) have comparable weights to HDPE (283 g). PETW and PETK cost $13/kg, lower than GFRP ($15-54/kg) and comparable to HDPE ($4-15/kg). Performance Benefits Better resistance to deformation (displacement at 1250N: PETK 7.16mm vs PP 10.91mm) Lower weight (PETK 245g vs GFRP 595g) Cost-effective (PETW/K: $13/kg vs GFRP: $15-54/kg) Strength Assessment of PET Fiber-Reinforced Composites for Prosthetic Sockets 2025-09-17

8. Study Limitations Load Capacity Constraints 125 kg Target Load 1250 N Maximum Recorded Displacement: 10.91 mm Maximum displacement recorded was 10.91 mm at 1250 N Target load of 125 kg was limited by aluminum socket rod bending Unable to evaluate ultimate load-bearing capacity Research Focus Study primarily explored PET fiber-reinforced composites as an alternative to: Expensive carbon, glass, and Kevlar fiber composites Durable thermoplastics (PP and HDPE) Manufacturing Process Limitations VARTM Process Limitations Vacuum-assisted resin transfer molding (VARTM) was used for composite socket manufacturing, which has limitations: Complex tooling requirements Sensitivity to fiber orientation Difficulty in achieving consistent quality VAT Process Limitations Vacuum-assisted thermal forming (VAT) for PP socket manufacturing has limitations: Requires preheating to 160°C for PP Forming time constraints Difficulty in achieving consistent dimensions Material Characterization Limitations Limited characterization of internal structure, focusing primarily on tensile testing rather than detailed structural analysis Strength Assessment of PET Fiber-Reinforced Composites for Prosthetic Sockets 2025-09-17

9. Future Recommendations Based on the findings of this study, we recommend the following next steps to further investigate PET fiber-reinforced composites for prosthetic sockets: Ultimate Strength Testing Use better socket rods for ISO 10328 standard testing to evaluate ultimate strength of PET fiber composites Manufacturing Process Optimization Adopt VAT process to PETW and PETK Durability Assessment Commercial Product Comparison Clinical Trials Automation & Customization Key Insight Strength Assessment of PET Fiber-Reinforced Composites for Prosthetic Sockets 2025-09-17

10. Conclusion Research Goal To explore PET fiber-reinforced composites as alternative materials for prosthetic sockets in resource-limited nations (LRNs) Key Findings Material Performance PETW and PETK composites showed superior performance compared to single-piece PP and HDPE materials Structural Integrity All socket types successfully met the target load capacity of 125kg Cost-Effectiveness PETW and PETK fabrics have material costs similar to GFRP, HDPE, and PP materials commonly used in LRNs Final Conclusions PET fiber-reinforced composites ( PETW and PETK ) can replace traditional materials in LRN prosthetic sockets These materials offer cost advantages compared to advanced composites The mechanical performance of PET composites is superior to single-piece thermoplastics PETW and PETK composites have similar specific stiffness to GFRP, HDPE, and PP materials PET fiber-reinforced composites are anideal choicefor developing durable prosthetics for amputees in resource-limited settings "PET fiber-reinforced composites offer a sustainable, cost-effective solution for prosthetic socket manufacturing in resource-limited nations." Strength Assessment of PET Fiber-Reinforced Composites for Prosthetic Sockets 2025-09-17

11. Kaitan Artikel dengan Rencana Disertasi Strength Assessment of PET Fiber-Reinforced Composites for Prosthetic Sockets 2025-09-17 Komponen Artikel Disertasi Judul Strength Assessment of PET Composite Prosthetic Sockets Tujuan investigates the feasibility of polyethylene terephthalate (PET) fibre -reinforced composites as a low-cost sustainable composite for producing functional lower-limb prosthetic sockets Latar Belakang Connection: Critical link between residual limb and prosthetic device Comfort: Proper fit and comfort ensure effective prosthetic function Load-bearing:Lower limb sockets various loads during walking Kebaruan Material Metodologi Fokus Analisa