J. Prasanna

Bio: J. Prasanna is an academic researcher from College of Engineering, Guindy. The author has contributed to research in topics: Electrical discharge machining & Machining. The author has an hindex of 4, co-authored 13 publications receiving 132 citations. Previous affiliations of J. Prasanna include Anna University.

Analysis of high aspect ratio small holes in rapid electrical discharge machining of superalloys using Taguchi and TOPSIS

Abstract: The main aim of this paper is to perform high aspect ratio small holes using rapid electrical discharge machining (rapid-EDM) of superalloys, namely Ti–6Al–4V and Inconel 718 with the tool materials like brass tubes and copper tubes. For employing the above-said materials, the performance characteristics such as material removal rate (MRR), tool wear rate (TWR) and overcut (OC) have been studied. In these investigations, DOE-Taguchi’s L9 orthogonal array has been utilized to build an experimental layout with the machining parameters such as current, on-time, off-time and capacitance. From the analysis, it is confirmed that there was a 40% increase in MRR, 282% decrease in TWR and 56% decrease in OC for rapid-EDM of Ti–6Al–4V material using the brass tubes than the copper tubes. Further, it is also validated that there is a 61% increase in MRR, 6% drop of TWR and 33% increase in OC for rapid-EDM of Inconel 718 material using brass tubes than the copper tubes. So, this comparative study has concluded that the machining of Ti–6Al–4V using brass tube has produced a maximum of MRR and minimum of TWR and OC. In Taguchi analysis, the individual effect of machining parameters on MRR, TWR and OC was studied. In addition, optimum combinations of machining parameters for MRR, TWR and OC were also discussed. Furthermore, multi-objective optimization was executed using TOPSIS to find good combination of machining parameters.

Advanced cutting tools and technologies for drilling carbon fibre reinforced polymer (CFRP) composites: A review

Abstract: Carbon fibre reinforced polymer (CFRP) composites have excellent specific mechanical properties, these materials are therefore widely used in high-tech industries like the automobile and aerospace sectors. The mechanical machining of CFRP composites is often necessary to meet dimensional or assembly-related requirements; however, the machining of these materials is difficult. In an attempt to explore this issue, the main objective of the present paper is to review those advanced cutting tools and technologies that are used for drilling carbon fibre reinforced polymer composites. In this context, this paper gives a detailed review and discussion of the following: (i) the machinability of CFRP including chip removal mechanisms, cutting force, tool wear, surface roughness, delamination and the characteristics of uncut fibres; (ii) cutting tool requirements for CFRP machining; and (iii) recent industrial solutions: advanced edge geometries of cutting tools, coatings and technologies. In conclusion, it can be stated that advanced geometry cutting tools are often necessary in order to effectively and appropriately machine required quality features when working with CFRP composites.

Application of cutting fluids in machining of titanium alloys—a review

Abstract: Titanium alloys are widely used in aerospace, biomedical, and other engineering areas due to their superior properties. However, machining of titanium alloys has always been a challenge due to the high temperatures and tool wear rates. Dry machining has a limited range of permissible cutting conditions and is hence not suitable for industrial production. As a solution, flood cooling using cutting fluids is conventionally used to reduce the cutting temperatures. However, it is often discouraged in light of the associated environmental and health hazards. In order to achieve sustainable machining, different strategies for applying the cutting fluids are developed. Some of the prominent methods include minimum quantity lubrication (MQL), minimum quantity cooled lubrication (MQCL), and cryogenic cooling. This paper provides a comprehensive review of the available recent literature on such studies. Each of these techniques and results obtained in the studies has been discussed with emphasis on the advantages and limitations of each method. Major conclusions drawn are that coated carbides are better and machinability is greatly affected by the microstructure of the material. MQL certainly improved compared to other methods while cryogenic or super cooled cutting fluid application (MQCL) has been found to be better for specific situations. Use of nanofluids for titanium is not very popular among the researchers.