Nowadays, polymer nanocomposite becomes a suitable alternative to conventional materials for lightweight and structural applications. Multiwall carbon nanotube (MWCNT)-reinforced epoxy composites possess superior electrical, mechanical, and thermal properties. In this article, drilling of MWCNT/epoxy nanocomposites has been investigated by considering varying parameters, namely, reinforcement wt% of MWCNT ( W ), speed ( N ), feed rate ( F ), and tool material ( M ). The response surface methodology (RSM) array was used for drilling experimentation. The mathematical modeling of drilling parameters was done by using artificial neural network. This study also highlights the integrated approach of principal components analysis (PCA)-embedded combined compromise solution method for multiobjective optimization of conflicting responses such as surface roughness (Ra), torque (Tr), and thrust force (Th). The PCA tool efficiently identified the response priority weight during the aggregation process. The confirmatory test was directed to evaluate the efficiency of the proposed hybrid module. The outcomes show a good agreement between the predicted and experimental value, and it can be endorsed to the polymer manufacturing sector for quality and productivity enhancements.

The present study developed a robust hybrid module for multi-criteria optimization of conflicting machining performances during milling of GO doped Epoxy/CFRP composites. Doping of GO radically increased the dispersion ratio which creates a better interaction of matrix and reinforcement. The machining behavior of these polymers significantly differs from metals and their alloys. The process constraints were considered as spindle speed (S), feed rate (F), depth of cut (D) and GO wt. percent (GO). Taguchi L9 OA was used in the combined optimization approach of AHP and TOPSIS. The optimum parametric combination was obtained as S2F2D1GO1 which shows substantial improvement in desired machining characteristics. The optimal results were verified through a confirmatory test, which shows good agreement with actual ones. The minimum roughness, cutting force and maximum MRR are found as 0.730 mm, 4.706 N, and 17.0484 mm³/s, respectively. The ANOVA inferred that S (79.55%) and F (4.80%) are the most important parameters for overall assessment value.

Polymethylmethacrylate (PMMA) in powder form is broadly used as bone cement in orthopedic applications due to its expanded mechanical, physical, and chemical properties. In this study, a hybrid PMMA biopolymer nanocomposite is developed by the supplement of graphene nanoplatelets (GnP) and hydroxyapatite (HA) powders of nano-size with combined loadings ranging from 0.5 to 2.5 weight %. Both materials were applied uniformly to reinforce commercial bone cement made of polymethylmethacrylate. The findings showed that adding 1.5 wt.% of combined HA and GnP nanoparticles to the powder of PMMA bone cement resulted in the expansion of flexural strength by 49.28%, the flexural modulus by 30.80%, the compression strength by 31.7%, and the compression modulus by 57.41%. The nanocomposite was characterized using Energy Dispersive X-Ray Analysis (EDS), Fourier transforms infrared (FTIR) spectroscopy, and X-ray diffraction (XRD) to study the distribution of reinforced nanoparticles. Scanning Electron Microscopy (SEM) analysis of the prepared samples and fractured surface shows the proper dispersion of nanofillers into the matrix phase and possible reasons behind fracture. The inclusion of GnP and HA in the PMMA enhances the mechanical performances required for biomedical components. Also, the SEM findings of the mechanically tested broken surface of the polymer nanocomposite samples demonstrated the feasibility of the proposed material for joint replacement surgical procedures and orthopedic implants.