Design of experiment is the method, which is used at a very large scale to study the experimentations of industrial processes. It is a statically approach where we develop the mathematical models through experimental trial runs to predict the possible output on the basis of the given input data or parameters. The aim of this chapter is to stimulate the engineering community to apply Taguchi technique to experimentation, the design of experiments, and to tackle quality problems in industrial chemical processes that they deal with. Based on years of research and applications, Dr. G. Taguchi has standardized the methods for each of these DOE application steps. Thus, DOE using Taguchi approach has become a much more attractive tool to practicing engineers and scientists. And since the last four decades, there were limitations when conventional experimental design techniques were applied to industrial experimentation. And Taguchi, also known as orthogonal array design, adds a new dimension to conventional experimental design. Taguchi method is a broadly accepted method of DOE, which has proven in producing high-quality products at subsequently low cost.

In the midst of a huge demand for high-precision miniaturized medical implants made up of potential biomaterials, the biomedical Ti-6Al-4V alloy meets the uncompromising standards for longevity, biocompatibility, and sterilizability required to interact with living cells in medical settings. This research tailored the existing capabilities of a traditional micro-electric discharge machining (µ-EDM) setup by adding 0, 2, 4, 6, 8, and 10 g/l bioactive zinc powder particle concentrations (PPCs) to the dielectric. A copper and brass micro-tool electrode (C-µ-TE and B-µ-TE) was employed in association with each PPC. Experiments were executed using the one-variable-at-a-time (OVAT) approach. Machining time and dimensional deviation were chosen as the response variables of Zn powder mixed-micro-EDM (Zn-PM-µ-EDM). According to the analytical findings, the combination of C-µ-TE and 6 g/l Zn PPC achieved 23.52%, 3.29%, and 17.96% lesser machining time, dimensional deviation, and recast layer thickness, respectively, compared to the B-µ-TE. The detailed study of this surface endorsed a significant modification in terms of improved recast layer thickness (26.44 µm), topography (Ra = 743.65 nm), and wettability (contact angle < 90 deg), suggesting its dental application. In addition, the observation of ZnO and TiO in X-ray diffraction and appealing in vitro cytocompatibility encourage the subsequent biological and therapeutic studies to validate the anticipated antiviral activity of the modified Ti-6Al-4V alloy surface against coronavirus (COVID-19).

The use of mineral-based cutting fluids in machining has the drawback of affecting the environment and industries are under pressures to reduce its use in favor of cleaner productions. In this regard, the vegetal-based cutting fluids can be a superior alternative, provided they improve the technical outcomes. In the milling process, dry cutting is commonly performed, however, the application of cutting fluids using the minimum quantity of lubricant (MQL) method has proven advantageous when compared with dry machining. Furthermore, in the midst of the availability of several cutting fluids in the market, the testing of their individual performance can ascertain their potential and effectiveness for a particular application. This study examined the performances of two vegetable-based and one mineral-based oils applied by the MQL method, followed by their comparison with dry cutting amid end milling of AISI 1045 steel with TiAlN-coated cemented carbide inserts. The cutting temperature, machining forces, power consumption, workpiece surface roughness, tool life, and tool wear mechanisms were chosen as the output parameters. The experiments were conducted using two cutting speeds (150 and 200 m/min) and feed rates (0.07 and 0.14 mm/tooth), and constant axial (1 mm) and radial depths of the cut (25 mm). The temperature was measured using a K-type thermocouple soldered to the part and an infrared camera. The power was monitored with a Fluke 435 energy analyzer, and the machining force components with a Kistler dynamometer. The worn inserts were inspected under a scanning electron microscope (SEM) to analyze the tool wear mechanism. The MQL-assisted application of the cutting fluids notably lowered the cutting temperature and increased the tools’ lives. However, the cutting fluids did not reflect any significant effect on the machining force, power consumption, or surface roughness. Among all the analyzed cutting conditions, the abrasive wear mechanism dominated, damaging the cutting edges, flank, and rake surfaces of the cutting tools. In addition, adhesive and diffusion wear mechanisms were also observed.