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An in-depth literature survey of machining study on fiber-matrix composites is presented in this review paper. The review work mainly focuses on optimization of machining parameters in composite materials with different machining factors. Conventional machining processes such as turning, drilling and milling as well as composite materials which are reinforced with fibers are considered in this study. Machining aspects on various fiber matrix composites has been carried out over a long period of time. In this review work, conflicting conditions of multi-attribute decision-making techniques and machining conditions are focused. The optimization study on machining parameters is done, considering both priori and posteriori approach including advanced optimization techniques. Optimization of machining parameters in fiber reinforced particulate composites has not been explored earlier. The review work on machining study of composites was not attempted earlier and hence this work provides valuable information for subsequent researchers to enhance the scope of research work in particle-reinforced polymer composites.

Higher damping with higher static stiffness is essential for improving the static and dynamic characteristics of machine tool structures. The structural vibration in conventional machine tools, which are generally made up of cast iron and cast steel, may lead to poor surface finish and the dimensional inaccuracy in the machined products. It leads to the investigation of alternative machine tool structural materials such as concrete, polymer concrete, and epoxy granite. Although epoxy granite has a better damping capacity, its structural stiffness (Young's modulus) is one-third as compared to cast iron. Therefore, the present work represents optimization of the structural design of the vertical machining center column by introducing various designs of steel reinforcement in the epoxy granite structure to improve its static and dynamic characteristics using experimental and numerical approaches. A finite element model of the existing cast iron vertical machining center column has been developed and validated against the experimental data obtained using modal analysis. Furthermore, finite element models for various epoxy granite column designs have been developed and compared with the static and dynamic characteristics of cast iron column. A total of nine design configurations for epoxy granite column with steel reinforcement are evolved and numerical investigations are carried out by finite element analysis. The proposed final configuration with standard steel sections has been modeled using finite element analysis for an equivalent static stiffness and natural frequencies of about 12–20% higher than cast iron structure. Therefore, the proposed finite element model of epoxy-granite-made vertical machining center column can be used as a viable alternative for the existing column in order to achieve higher structural damping, equivalent or higher static stiffness and, easy and environmental-friendly manufacturing process.

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Nowadays, natural fibre-reinforced composites find applications in almost all engineering fields. This work is an attempt to realise improvement in dynamic characteristics of micro lathe bed using Himalayan nettle (Girardinia heterophylla) polyester (NP) composite as an alternate material. In order to study and validate the improvements envisaged, a cast iron micro lathe bed is considered as reference. Numerical (FE) model of the cast iron micro lathe bed was developed and validated through experimental static and modal analysis. Finite element analysis of the micro lathe bed with the existing cast iron material as well as with nettle-polyester composite as alternate material was also carried out using worst case cutting forces, and based on the relative performances, the need for form design modification for the proposed material was identified. To enhance the bending and torsional stiffness of the nettle-polyester composite lathe bed, various cross sections and rib configurations were studied and the best among them was identified and the same was implemented in the nettle-polyester composite micro lathe bed design. Finite element analysis of the newly designed nettle-polyester composite micro lathe bed was performed and the improvements in dynamic characteristics were evaluated. The newly designed nettle-polyester composite micro lathe bed was fabricated and the predicted enhancement in static and dynamic characteristics was verified experimentally. The studies indicated that nettle-polyester composite could be considered as a suitable alternate to cast iron structures in machine tools.