پديدآورندگان :
Soleyman Elyas School of Mechanical Engineering, College of Engineering, University of Tehran, Tehran, Iran , Rahmatabadi Davood School of Mechanical Engineering, College of Engineering, University of Tehran, Tehran, Iran , Baghani Mostafa School of Mechanical Engineering, College of Engineering, University of Tehran, Tehran, Iran , Baniassadi Majid School of Mechanical Engineering, College of Engineering, University of Tehran, Tehran, Iran
چكيده فارسي :
In this work, for the first time, PET-G commercial filament is employed for 4D printing of novel shape memory polymer (SMP). PET-G was found to be an amorphous SMP with net points of tight-knitted physical entanglements decelerating the stress relaxation. Printing parameters had a significant effect on the self-morphing behavior as well as shape and stress recovery. Birefringence studies using polarized light microscopy (PLM) revealed that the fused deposition modeling (FDM) process induces a higher pre-strain in the bottom layers than in the top ones, resulting in a downward self-bending. It was revealed that lower printing temperatures and higher printing speeds enhance the self-bending and shape recovery characteristics. All shape fixity ratios were higher than 82%, with a maximum of 95.83% for samples printed with ± 45 raster angles. The sample with the highest self-bending exhibited the maximum recovered stress of 1.24 MPa.
