Effect of process parameters on mechanical properties of additive manufactured SMP structures based on FDM

As a new concept and multidisciplinary research area that combines advanced manufacturing, materials science and mechanics, 4D printing has attracted academic interest in the recent years. Shape Memory Polymer (SMP) is widely used in 4D printing due to its high stiffness and fast response. In order to make better analysis and research on additive manufacturing of SMP structures based on FDM, the DMA, DSC and TMA tests were conducted first to determine the basic thermodynamic properties of SMP. And then nine parameters, divided into three groups including printing parameters, temperature parameters and structural parameters were examined to character and assess the effect on the mechanical properties of SMP samples, respectively. The results show that the best parameters combination of temperature and printing parameters for the SMP printing is that platform temperature T ( P ) = 65 degrees C, nozzle temperature T ( N ) = 210 degrees C, feed rate Fr = 50 mm/s, layer thickness Lt = 0.18 mm. Compared with temperature and printing parameters, the structural parameters directly affect the tensile strength of the specimen with improve of 17.298 MPa while these two are 3.639 and 5.528 MPa. The tensile strength of the specimen can be effectively improved through adjusting the structural parameters.