3D printing represents a great opportunity for biocomposites to be developed for the first time on the same time scale as their synthetic counterparts. The purpose of this article is a global investigation of the relationship between slicing parameters (i.e. Layer Height (LH), Interfilament Distance (ID), Number of Trips (NT), Number of Layers (NL)), microstructure and induced tensile properties in order to propose 3D printed continuous flax/PLA biocomposites with tailored mechanical properties.

The Layer Height controls filament compaction during printing. The decrease in LH from 0.6 to 0.2 mm results in a reduction in layer thickness, a decrease in porosity, and an increase in tensile properties (+210% for stiffness and strength). The increase in NL from 1 to 10 results in higher compaction ratio due to the compaction effect of layer n on layer n-1 and superior tensile properties (+50% in modulus and +73% in strength).

NT and ID control the space available for the filament between the nozzle and adjacent filaments respectively. This significantly affects the average layer thickness and the overall geometry of the sample. Increasing NT from 1 to 18 reduces the space available for the polymer matrix flow for each filament due to the neighboring effect. Generally, the 3D printing process with continuous-flax/PLA composites provides a wide range of tensile properties that are still considerably higher than the current published values for printed short natural fiber composites and in the same range as printed continuous glass fiber/PA composites.

3D打印为生物复合材料的首次开发提供了巨大的机会，与生物合成复合材料的开发时间相同。本文的目的是对切片参数（即层高（LH），纤丝间距离（ID），行程数（NT），层数（NL）），组织和拉伸强度之间的关系进行全局研究。为了提出具有定制机械性能的3D打印连续亚麻/ PLA生物复合材料。

层高控制打印过程中的细丝压紧。LH从0.6毫米减小到0.2毫米导致层厚度减小，孔隙率减小和拉伸性能提高（刚度和强度为+ 210％）。从由于层的压实作用1至10导致较高的压实比在NL的增加Ñ在层n-1个和优异的拉伸性能（模量+ 50％和+ 73％的强度）。

NT和ID分别控制喷嘴和相邻细丝之间的细丝可用空间。这会明显影响样品的平均层厚度和整体几何形状。NT由于相邻效应而从1增加到18减少了每根长丝可用于聚合物基质流动的空间。通常，具有连续亚麻/ PLA复合材料的3D打印工艺可提供广泛的拉伸性能，其拉伸性能仍远高于印刷短天然纤维复合材料的当前公布值，并且与印刷连续玻璃纤维/ PA复合材料的范围相同。