Mozammel Mia

Response surface and neural network based predictive models of cutting temperature in hard turning

Graphical abstract

Influence of single and dual cryogenic jets on machinability characteristics in turning of Ti-6Al-4V

Based on the necessity of a solid study on the orientation of liquid nitrogen jets in turning, this study investigates the specific cutting energy, surface roughness, chip morphology, chip–tool interface temperature, tool life, and wear of coated carbide tool under the single and duplex jets liquid nitrogen for congenial turning of a hard-to-cut superalloy (Ti-6Al-4V). The single jet was aimed at rake face, whereas the duplex jets were impinged at rake and flank surfaces, simultaneously. Results showed that the later coolant employment method ensured the most favorable machining characteristics, which can be accredited to the extreme cooling by liquid nitrogen jets, in terms of reduced specific cutting energy, temperature, roughness, and admittedly, an increased life of tools. The duplex liquid nitrogen jets prolonged tool life by 60% and 30% compared to dry and single jet assistance, respectively. However, no visible difference in chip formation has been noticed. In recapitulation, the duplex liquid nitrogen jets are established as sustainability promoter as—tool life is increased thus tool cost is reduced, required energy is lessened, temperature is pacified, surface quality is improved, and above all, favorable machinability of Ti-6Al-4V superalloy is attained.

Effects of cutting parameters and machining environments on surface roughness in hard turning using design of experiment

Hard turning is gradually replacing the time consuming conventional turning process, which is typically followed by grinding, by producing surface quality compatible to grinding. The hard turned surface roughness depends on the cutting parameters, machining environments and tool insert configurations. In this article the variation of the surface roughness of the produced surfaces with the changes in tool insert configuration, use of coolant and different cutting parameters (cutting speed, feed rate) has been investigated. This investigation was performed in machining AISI 1060 steel, hardened to 56 HRC by heat treatment, using coated carbide inserts under two different machining environments. The depth of cut, fluid pressure and material hardness were kept constant. The Design of Experiment (DOE) was performed to determine the number and combination sets of different cutting parameters. A full factorial analysis has been performed to examine the effect of main factors as well as interaction effect of fact...

Machinability Investigations of Inconel-800 Super Alloy under Sustainable Cooling Conditions

With regard to the manufacturing of innovative hard-machining super alloys (i.e., Inconel-800), a potential alternative for improving the process is using a novel cutting fluid approach. Generally, the cutting fluids allow the maintenance of a better tool topography that can generate a superior surface quality of machined material. However, the chemical components of fluids involved in that process may produce harmful effects on human health and can trigger environmental concerns. By decreasing the cutting fluids amount while using sustainable methods (i.e., dry), Near Dry Machining (NDM) will be possible in order to resolve these problems. This paper discusses the features of two innovative techniques for machining an Inconel-800 superalloy by plain turning while considering some critical parameters such as the cutting force, surface characteristics (Ra), the tool wear rate, and chip morphology. The research findings highlight the near-dry machining process robustness over the dry machining routine while its great potential to resolve the heat transfer concerns in this manufacturing method was demonstrated. The results confirm other benefits of these methods (i.e., NDM) linked to the sustainability aspects in terms of the clean process, friendly environment, and permits as well as in terms of improving the manufacturing characteristics.

Synthesis, Characterization, Corrosion Resistance and In-Vitro Bioactivity Behavior of Biodegradable Mg–Zn–Mn–(Si–HA) Composite for Orthopaedic Applications

Recently, magnesium (Mg) has gained attention as a potential material for orthopedics devices, owing to the combination of its biodegradability and similar mechanical characteristics to those of bones. However, the rapid decay rate of Mg alloy is one of the critical barriers amongst its widespread applications that have provided numerous research scopes to the scientists. In this present, porous Mg-based biodegradable structures have been fabricated through the hybridization of elemental alloying and spark plasma sintering technology. As key alloying elements, the suitable proportions of silicon (Si) and hydroxyapatite (HA) are used to enhance the mechanical, chemical, and geometrical features. It has been found that the addition of HA and Si element results in higher degree of structural porosity with low elastic modulus and hardness of the Mg–Zn–Mn matrix, respectively. Further, addition of both HA and Si elements has refined the grain structure and improved the hardness of the as-fabricated structures. Moreover, the characterization results validate the formation of various biocompatible phases, which enhances the corrosion performance and biomechanical integrity. Moreover, the fabricated composites show an excellent bioactivity and offer a channel/interface to MG-63 cells for attachment, proliferation and differentiation. The overall results of the present study advocate the usefulness of developed structures for orthopedics applications.