Patient-specific implants are well known for fixing the fracture for bone repairs. However, the exact fixation of the fabricated implant to the patients is a challenging task. To overcome this problem, in the present study two kinds of designs are developed and fabricated. Based on the exact fitting to the patient’s oral system, the best design is selected to fabricate. Computed tomography (CT) scan data of the patient oral anatomy is converted into a 3D model using the DICOM Software “Slicer 3D.” The patient-specific maxillofacial implant is fabricated using fused filament fabrication (FFF) and direct metal laser sintering (DMLS) techniques. Before fabricating real time product, a prototype is fabricated at the initial stage using FFF. Later, stress distribution and displacement of the implant was investigated using a FEM simulation. The conclusion of the present work results are potential for FFF of patient-specific implants out of Ti-6Al-4V.

In this study, a biodegradable Mg-Zn-Nd-Gd alloy was processed via multi-directional forging (MDF) to evaluate its microstructural evolution, mechanical performance, and corrosion behavior. Electron backscattered diffraction (EBSD) analysis was conducted to evaluate the influence of grain size and texture on mechanical strength and corrosion resistance. The average grain size decreased significantly from 118 ± 5 μm in the homogenized state to 30 ± 10 μm after six MDF passes, primarily driven by discontinuous dynamic recrystallization (DDRX). Remarkably, this magnesium (Mg) alloy exhibited a rare synergistic enhancement in both strength and ductility, with ultimate tensile strength (UTS) increasing by ~59%, yield strength (YS) by ~90%, while elongation improved by ~44% unlike conventional severe plastic deformation (SPD) techniques that often sacrifice ductility for strength. This improvement is attributed to grain refinement, dispersion strengthening from finely distributed Mg₁₂Nd and Mg₇Zn₃ precipitates, and texture weakening, which facilitated the activation of non-basal slip systems. Despite the mechanical improvements, electrochemical corrosion testing in Hank’s balanced salt solution (HBSS) at 37 °C revealed an increased corrosion rate from 0.1165 mm/yr in homogenized condition to 0.2499 mm/yr (after six passes of MDF. This was due to the higher fraction of low-angle grain boundaries (LAGBs), weak basal texture, and the presence of electrochemically active fine Mg₇Zn₃ particles. However, the corrosion rate remained within the acceptable range for bioresorbable implant applications, indicating a favorable trade-off between mechanical performance and degradation behavior. These findings demonstrate that MDF processing effectively enhances the strength–ductility synergy of Mg-rare earth alloys while maintaining a clinically acceptable degradation rate, thereby presenting a promising route for next-generation biomedical implants.

The wear performance of partially oxidized NiCr and NiCrBSiFe coatings were investigated by varing load and speed. The partial oxidized powders were processed from the alloy powder using a flame spray process that involved spraying into distilled water. The partially oxidized powder was then plasma-sprayed onto MDN321 steel. The coatings were characterized for adhesive strength, microhardness, and density. The wear behavior was evaluated at disc speeds of 1, 2, and 3 m/s, with loads ranging from 10 to 50 N, over a 3000 m sliding distance. A significant difference in wear rates between the coating and substrate was observed. Operating at a sliding velocity of 1 m/s under a 10 N load, the substrate's wear rate was found to be 3.56 times higher than that of the NiCrBSiFe coating, whereas for NiCr coating, it was 2.78 times higher. Wear rate coefficient performance shift takes place between the coatings at 12 N-m/s, product of applied load (C) and sliding velocity (V). In NiCrBSiFe coating, the wear mechanism observed at lower speeds and loads is micro-brittle and mechanism shifts to abrasive wear at higher speeds and loads. In the NiCr partially oxidized coating, the wear mechanism observed involves spallation of the coating at higher loads and adhesive wear at lower loads. Thermo gravimetric analysis of the coatings revealed a weight loss percentage of 1.42 for NiCrBSiFe and 14.09 for NiCr coatings. These findings highlight the NiCrBSiFe partially oxidized coating as being tenfold more stable at high temperatures compared to the NiCr partially oxidized coating.