<p>The exponential rise of 3D printing in the recent years has revolutionized the manufacturing and production industry in more than one way. Advancement in 3D-printing technologies has also led to an enhancement in a component’s strength, stiffness, and weight. Among other widely used materials, polymers such as Polylactic Acid + (PLA +) which is an enhanced version of the conventional PLA offers several advantages, such as affordability, sustainability, and ease of use. An important parameter in determining the mechanical properties of 3D-printed components is infill density. Infill density is the amount of an object’s inner volume that is filled by the material. This research paper aims to evaluate the relation between infill density and structural integrity of the component. Using 3D printer, samples with infill densities of 25%, 50%, and 100% were fabricated and subjected to standardized tensile testing. Additionally, Field Emission Scanning Electron Microscopy (FESEM) was used to view the fracture surfaces at a microscopic scale and it provided valuable insights into the fracture behavior of the components. The study confirms that both infill density and pattern significantly influence the mechanical properties of 3D-printed parts. The results reveal that upon increasing infill density from 25 to 100%, a 168% increase in tensile strength and 20.34% reduction in percentage of elongation are observed. By gaining a proper understanding of the relation between infill density and structural integrity, 3D-printed components can be used in practical day-to-day applications, and also, by understanding how internal geometry influences material failure, it can be useful in devising techniques that can contribute to more efficient additive manufacturing processes.</p> Graphical abstract <p></p>