| Dan DOBROTĂ1, Sergiu LAZĂR2, Anca-Loredana DECA3
Abstract. This study presents a comparative evaluation of hemp fibers and sheep wool fibers (Țurcană breed) used as reinforcements in polymer-matrix composites, focusing on mechanical performance, thermal behavior and durability under thermal shock. The experimental program included tensile and compression testing, density measurements, water absorption analyses and morphological investigations by scanning electron microscopy (SEM), carried out before and after an accelerated aging process between −20 °C and +100 °C, lasting 500 hours. The results show that the wool-reinforced composites exhibit superior thermal insulation, with a reduction in thermal conductivity of approximately 12–15% compared to those based on hemp, as well as a moderate increase in tensile strength of about 8%. However, SEM analysis reveals weaker fiber–matrix interfacial adhesion in the wool case, reflected by pronounced pull-out phenomena and an interfacial strength approximately 10% lower. Hemp-reinforced composites display superior compressive performance, with values up to 20% higher, owing to their porous structure. After aging, the wool composites retain over 92% of their tensile strength and register an increase of about 5% in compressive strength, confirming their superior thermal stability. Keywords: polymer composites; hemp fibers; Țurcană wool; ecodesign; thermal aging; SEM analysis; mechanical strength. DOI 10.56082/annalsarscieng.2026.2.128 Read full article 1Prof., PhD. Department of Industrial Engineering and Management, Faculty of Engineering, Lucian Blaga University of Sibiu, 550024 Sibiu, Romania; Academy of Romanian Scientists, Ilfov Street 3, 050045 Bucharest, Romania (e-mail: dan.dobrota@ulbsibiu.ro). 2PhD. Candidate Eng. Faculty of Engineering, Lucian Blaga University of Sibiu, 550024 Sibiu, Romania; (e-mail: sergiu.lazăr@ulbsibiu.ro). 3PhD. Candidate Eng. Faculty of Industrial Engineering and Robotics, National University of Science and Technology Politehnica Bucharest, 060042 Bucharest, Romania (e-mail:anca_loredana.deca@upb.ro), |
PUBLISHED in Annals Academy of Romanian Scientists Series on Engineering Sciences
ISSN PRINT 2066 – 6950 ISSN ONLINE 2066 – 8570 |
