Manufacturing Technology Today

Haider Nasreen ¹, S. Rajendra Boopathy ², M. Murugan ¹, S. Zubaida Kathoon Bee ¹

Affiliations
1 Dept. of Mech. Engg., B S A Crescent Engg. College, Chennai, IN
2 Dept. of Mech. Engg., College of Engg., Guindy, Chennai, IN

Abstract

This paper presents the simulation of orthogonal metal cutting of 6061 T6 Aluminium alloy using Hypermesh and LS-Dyna to study the effect of the edge radius on cutting forces and chip formation. The constitutive material model Elastic Plastic Hydrodynamic was used to model the work piece. The capability of this model to predict cutting forces, shear angle and chip curvature was investigated. Design of Experiments principle was used to study the effect of the parameters on cutting edge performance. The trends of the simulated results were in good agreement with the generally observed theoretical and experimental results. The model can also be used as a numerical tool for optimizing the edge radius. The effect of edge radius and other cutting conditions on the chip curl and the shear angle were also investigated.

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S. Mohamed Nazeer ¹, M. Murugan ¹, S. Rasool Mohideen ¹, Y. V. N. Narasimma Moorthy ²

Affiliations
1 Dept of Mechanical Engg., BSA Crescent Engg. College, Chennai, IN
2 BHEL R&D Ltd, Hyderabad, IN

Abstract

Cryogenic treatment is a process of treating materials, at temperatures well below 0°C to achieve improved mechanical properties. Cryogenic treatment was observed to enhance the mechanical properties of various materials like tool steels, bearing materials, carbon fiber composites and copper resistance welding electrodes. Application of cryogenic treatment as a post weld treatment to weldments is a new area to be studied. In the present investigation, 2.25 Cr 1 Mo low carbon low alloy steel weldments were cryogenically treated and their mechanical behavior evaluated. Changes in microhardness, Charpy V notch toughness and changes in the microstructure were studied. The performance of as welded, tempered, long cycle cryogenic treated and tempered and long cycle cryogenic treated weldments were compared. J-integral as a measure of fracture toughness of the weldments was computed and compared. The long cycle cryogenic treatment was found to result is substantial increase in impact toughness with the marginal reduction in micro hardness. At the micro structural level, that formation of acicular ferrite, grain refinement and precipitation of alloying elements were found to be the basic mechanisms responsible for the increased impact toughness.

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N. Muthukrishnan ¹, Varun Krishnakumar ², S. Kailash ³, K. Prahlada Rao ⁴, M. Murugan ⁵

Affiliations
1 Dept. of Mech. Engg., Sri Venkateswara College of Engineering, Sriperumbudur, IN
2 GTRE (DRDO), Bangalore, IN
3 XLRI, Jamshedpur, IN
4 JNTU College of Engineering, Anantapur, IN
5 BSA Crescent Engineering College, Chennai, IN

Abstract

Aluminium Silicon Carbide (Al.SiC) metal matrix composite (MMC) materials have a set of mechanical and physical properties that are ideally suited for applications in aerospace, automobile industries. Despite the superior set of mechanical and physical properties, the usage of MMC's in industry is still limited owing to difficulties in machining. To overcome this barrier, this paper performs a thorough study about the machinability of Al-SiC (MMC) with PCD insert tool to establish machining guidelines.The focus of the investigation is to determine the optimum machining conditions by adjusting the spindle speeds, depth of cut and feed, and observing the corresponding behaviour of cutting force, surface imperfections, power consumed, and MRR. The worn out tool is subjected to microscopic analysis to evaluate the wear on the tool.On completion of the experimental test, an artificial neural network (ANN) is used to validate the results obtained and also to predict the behaviour of the system under any condition within the operating range.

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T. Alwarsamy ¹, V. Selladurai ², P. Thangavel ², M. Murugan ³, A. Gopal Das ³

Affiliations
1 GCT, CBE, IN
2 CIT, CBE, IN
3 GCT Campus, Coimbatore-641013, IN

Abstract

In the turning operation, chatter or vibration is a frequent problem, which affects the surface finish and tool life. In all cutting operations like turning, boring and milling vibrations are induced due to the deformation of the workpiece, this implies economical disadvantage. The main objective of the proposed work is to design damped tool holder for existing machine tools with low cost fabrication techniques. In this investigation, improvement of the damping capability of boring tool and suppression of chatter vibration using lead damper and Impact damper are analyzed. The lead damper Inertia mass of the boring tool has been Increased to suppress the chatter vibration. In impact damper kinetic energy of free mass is dissipated. Finite element analysis is performed to study dynamic behavior of composite tool holder, the effects of overhang length of boring tool with lead damper, and the effects of impact damper in boring tool was investigated.

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