PSI - Issue 83

Wong Kam Chee et al. / Procedia Structural Integrity 83 (2026) 14–27

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2. Methods and Materials This research starts with the generation of the TPMS lattice model in the nTopology student version, then followed by meshing the model and simulating the generated model. The steps included generation of TPMS lattice by mathematical expression, set material as Ti6Al4V and boundary condition of 1000N on the top plate and fixing the bottom plate. Finite Element Analysis (FEA) is done on the lattice structure to analyse the behavior of the lattice under compressive load, homogenization characteristics, and cantilever beam test. The steps will be explained in the following subsections. Lattice Model Generation In this study, two TPMS structures and one hybrid lattice structure were generated using nTopology, which are Schwarz Primitive, Gyroid, and Schwarz Primitive- Gyroid hybrid. The cube size was fixed to be 10mm 3 and the unit cell size was set to 5mm, which forming a 2 x 2 x 2 unit cell cube and was the main structure that will be used in the simulation as shown in Figure 1. Two plates (top and bottom plates) with area of 12.5mm 2 and 1mm plate thickness are then generated by using the multiply block and are set as a Boolean union. The lattice body is then generated using the new volume of the bounding box and the thickness is set to 0.2mm. It is then combined with the top and bottom plate using the Boolean intersect function. The TPMS lattice model is then completed, and the lattice structure is ready to be simulated. 2.1

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Figure 1. (a) Schwarz P; (b) Gyroid; (c) Hybrid

2.2 Material Selection Biomaterials are organ-repairing materials that are used in tissue engineering to replace tissue of a particular organ. The characteristics of the biomaterials are printable (by using additive manufacturing), non-cytotoxic (harmfulness to cells), osseointegration (providing bone growth in the implant), and biodegradable (tissue regeneration) [24]. Titanium alloy and cobalt alloy are common biocompatible materials used in hip implant fabrication. The development of Aluminum (Al) and Vanadium (V) free Titanium (Ti) alloy has been the research focus on biocompatible material for orthopedic joint replacements. Ti alloy is frequently used as a material for orthopedic implants due to its superior mechanical properties, biocompatibility, and corrosion resistance [25]. Cobalt alloys are high corrosion resistance and wear resistance biomaterial [26]. Cobalt-chromium alloy was among one of the biocompatible materials introduced in artificial hip joint manufacturing [27]. Cobalt-chromium and titanium alloys are favorable in implant manufacturing, specifically, femoral stem fabrication [28]. Ti6Al4V is chosen as material in this study as it is biocompatible and has excellent mechanical properties. Meshing Meshing is an important step for the model to be ready for analysis as it allows accurate simulation of the behaviour of the structure in various conditions and generates reliable analysis and predictions. There are many shapes for the meshing for the different dimensions. For example, lines for one-dimensional meshing, triangles and quadrilaterals for two-dimensional meshing, and tetrahedra and triangular prisms for three-dimensional meshing. The mesh can be further categorized into structured mesh and unstructured mesh and can be used according to the geometry needs. Figure 2 shows the mesh convergence study to obtain the optimum mesh edge length for the simulation. There are a few parameters that can be adjusted when meshing in nTopology, which are edge length, 2.3