The effect of the interlayer time and deposition speed on the tensile properties of material extrusion components

This study investigates the influence of the substrate temperature in material extrusion (MEX) on tensile behavior of PLA samples. A full factorial experimental plan was conducted by varying the deposition speed and the interlayer time. Infrared thermography was conducted to determine the influence of the deposition conditions on the temperature of the substrate just before the deposition of the next layer. Tensile tests were conducted along the “upright direction” to determine the influence of the thermal history on the interlayer adhesion. The results indicate the strong influence of the interlayer time on the thermal history and the mechanical behavior. The temperature of the substrate before subsequent overlying deposition was mainly influenced by the interlayer time, while it was less affected by the deposition speed. The Young modulus of the samples was poorly affected by the adopted process conditions; on the other hand, the maximum strength and the elongation at rupture were strongly affected by the interlayer time. The identified variances in mechanical behavior underscore the pivotal significance of sample dimensions in dictating the ultimate mechanical characteristics of vertically oriented samples. These outcomes illuminate the intricate interaction between deposition speed and interlayer duration, highlighting their substantial influence on mechanical performance.