Nanoparticles dispersed in lubricants are being studied for their ability to reduce friction and wear. This paper examines SAE 5W-30 oil enhanced with dispersed graphene nanoplates for tribological and rheological properties. Graphene nanoplate (GNs) concentration effects on the rheological and tribological properties of 5W-30 base oil (0.03, 0.06, 0.09, 0.12, and 0.15 wt percent) were tested. Under various loads, a four-ball testing model was used to conduct a tribological analysis (200, 400, 600, and 800 N). Kinematic viscosity is calculated, and base oil and nanofluid-added 5W30 lubricant are compared for thermal conductivity and flashpoint. Wear scar and coefficient of friction improved by 15% and 33% with nano-additives. When related to the base oil, the flashpoint, thermal conductivity, kinematic viscosity, and pour point all increased, by 25.4%, 77.4%, 29.9%, and 35.4%, respectively. The addition of GNs improved the properties of 5W30 engine oil.

Fused deposition modeling (FDM) is a layered manufacturing (LM) process in which progressive 2D layers of material are kept making a 3D part. To optimize the building operation, the investigation is necessary to study the effect of process parameters. This study examines the impact of three filling patterns, “triangles,” “cross,” and “cross 3D,” with three filling densities (25%, 50%, and 75%) in three orientations (“flat,” “on long edge,” and “on short edge”) on ultimate tensile strength (UTS), hardness and the printing time of polylactic acid (PLA) material. This work built tensile specimens according to ASTM D638 on an open‐source 3D printer. The UTS was collected using a WDW‐2000 computer control electronic universal testing machine. The hardiness value was also measured using Shore A hardness durometers DIN 53505 and ASTM D2240. In addition, the building time was conducted by implementing the “Cura 4.6” slicer software. The results show that the filling pattern, orientation, and density at which the part is built significantly affect the strength, hardness, and building time. For light structure parts with 25% density, it is recommended to build parts with “triangles” “on long edge” to obtain the highest strength (31.02 MPa), which improved by 74.3%, with 281 HV at the minimum time (1 h:10 min), which was reduced by 46.1%. For dense structure parts, “triangles” and “on long edge” are recommended to give the highest strength (42.12 MPa), which can be improved by 69.8% (282 HV) at the minimum time (1 h:35 min), which was reduced by 36.2%. For medium construction, 50% of the parts can be built by the following parameters: “cross” and “on long edge” to obtain the highest strength (38.48 MPa) with 283 HV at the minimum possible time (1 h:55 min). The study could help with the growth of producing mechanically functional parts, such as prosthetics, using LM. In addition, the part can be built with high strength, hardness, and minimum building time, which is useful information for the best utilization of the 3DP machine. Also, the chosen parameters optimize the building process with little human intervention.

Recently, developing 3D printing (3DP) technologies have been substantiallyincreased, because its advantages toward the direct fabricating of 3D physical modelfrom the CAD system. Although several advantages over the subtractive method, thereare still many difficulties and problems for building a precise and efficient part. Buildingtime and Accuracy are two important concerns in 3DP. To speed up the buildingprocess and improve the accuracy at the same time, an algorithm based onmathematical models will be presented. The algorithm presents variable slicingstrategy by adjusting the layer thickness to consider the curvature and flatness of the3D CAD surfaces, in order to reduce the number of building layers, staircase effect,and consequently decrease the building time and cost. Through this proposedanalytical study and the results, the number of layers were saved by 54% that willdecrease the building time by the same percentage.

Fused Deposition Modeling (FDM) is a Layered Manufacturing (LM) process in which progressive 2D layers of material are kept making a 3D part. To optimize the building operation, investigation is necessary to study the effect of process parameters. This study examines the impact of three filling patterns “Triangles”, “Cross” and “Cross 3D” with three filling densities (25%, 50%, and 75%) in three orientations (“Flat”, “on long edge”, and “on short edge”) on Ultimate Tensile Strength (UTS), hardness and the printing time of Polylactic Acid (PLA) material. In this work, tensile specimens were built according to ASTM D638 on an open-source 3D printer. The UTS were collected using WDW-2000 computer control electronic universal testing machine. Also, the hardiness value was measured using shore A hardness durometers DIN 53505 and ASTEM D2240. In addition, the building time was conducted by implementing “Cura 4.6.” slicer software. The results show that the filling pattern, orientation, and density, at which the part is built, have a significant effect on the strength, hardness, and building time of the part. for light structure parts 25% density, it is recommended to build part with “Triangles” “on long edge” to obtain the highest strength (31.02MPa) which improved by 74.3%, with (281HV) at min. time (1hr:10min) which reduced by 46.1%. For dense structure parts, “Triangles”, “on long edge” are recommended to give the highest strength (42.12MPa), which be improved by 69.8%, (282HV) at min. time (1hr:35min) which reduced by 36.2%. For medium construction 50% the parts can be built by the following parameters “Cross”, “on long edge” to obtain the highest strength (38.48MPa) with (283HV) at min. possible time (1hr:55min).

This paper investigates the influence of various filling strategies and infill percentages on the ultimate tensile strength (UTS) and build time of polylactic acid (PLA) objects produced using Fused Deposition Modeling (FDM). The research focused on three infill percentages: 25%, 50%, and 75%, along with four distinct filling strategies: Cross, Cross 3D, Triangles, and Tri-Hexagon. Tensile test specimens were prepared following ASTM D638 standards, with Ultimaker Cura software employed to determine build times. The findings revealed that the Triangles filling strategy provided the highest UTS at 50% and 75% infill, while the Cross-3D strategy consistently delivered the lowest UTS across all percentages. Regarding build time, the Triangles and Tri-Hexagon strategies were the most efficient, offering the shortest building durations. The study concludes that UTS improves as the infill percentage increases, and it ranks the strategies based on both strength and build time, offering practical insights for optimizing FDM printing parameters for PLA materials, and balancing mechanical performance with manufacturing efficiency.