Manufacturing Technology Today

G. Rajashekar Reddy ¹, Sunil Magadum ², M. Chellamalai ², N. Balashanmugam ²

Affiliations
1 Dept. of Mech. Engg., NITK, Surathkal, IN
2 Central Manufacturing Technology Institute (CMTI), Bangalore, IN

Abstract

Femtosecond laser micromachining of rectangular grooves on AISI3415 steel is investigated at 150 fs pulse duration and at a wavelength of 775nm. In the present work, Laser process parameters such as spot size, feed rate and number of passes are optimized considering the multiple responses such as surface roughness (Ra) and depth of groove based on orthogonal array with grey relational analysis. A grey relational grade is calculated using grey analysis and process parameters are optimized based on signal to noise ratio. To validate the experimental result, verification test is performed. Experimental outcomes have proved that the responses in femtosecond laser micromachining can be enhanced efficiently through this approach.

Keywords

Femtosecond Laser, Micromachining, Laser Spot Size, Taguchi Grey Relational Analysis.

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Sunil Magadum ¹, M. Chellamalai ², N. Balashanmugam ¹

Affiliations
1 Central Manufacturing Technology Institute (CMTI), Tumkur Road, Bengaluru, IN
2 Ultra Precision Engineering Dept, Central Manufacturing Technology Institute (CMTI), Tumkur Road, Bengaluru, IN

Abstract

Since its invention in 1960, laser has been widely used in many fields, such as scientific research, medical treatment, industry and military. Excimer lasers are an important family of gas lasers that were firstly commercialized in the 1970s. The most common excimer lasers use rare-gas monohalides such as KrF, ArF & XeCl and have a wavelength in ultraviolet (UV) range. The applications of excimer laser are very broad with new applications continuously coming out. This paper addresses novel applications of an excimer laser (248 nm & 193 nm wavelength, 20 ns pulse duration) in micromachining.

Keywords

Excimer Laser, Micromachining, MEMS, HAZ.

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K. Kiran Kumar ¹, V. A. P. Sarma ¹, N. Balashanmugam ¹, K. B. Vinaya Kumar ², G. M. Hegde ³, K. Rajanna ², M. M. Nayak ³, N. S. Dinesh ⁴

Affiliations
1 Nano Manufacturing Technology Centre, CMTI, Bangalore, IN
2 Department of Instrumentation and Applied Physics, IISc, Bangalore, IN
3 Centre for Nano Science and Engineering, IISc, Bangalore, IN
4 Department of Electronic Systems Engineering, IISc, Bangalore, IN

Abstract

In this work, we present the fabrication of hollow steel microneedles for transdermal drug delivery. Hollow steel microneedles are fabricated by laser ablation technique using femto second laser micromachining. A 4x3 array of rectangular microneedles with circular holes are fabricated. The processed hollow steel microneedles are 700 μm in height with 60 μm and 150 μm inner and outer diameters respectively.

Keywords

Micro-Needles, Steel, Femto Second Laser.

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K. Niranjan Reddy ¹, N. Balashanmugam ¹, P. V. Shashikumar ¹

Affiliations
1 Central Manufacturing Technology Institute, Tumkur Road, Bangalore, IN

Abstract

With the objective of catering the R&D needs of machine tools and allied areas in focus, along with the basic infrastructure of the institute, various laboratories including metrology laboratory were setup in CMTI to support developmental activities and to assist prototype workshop. With the advancement of time, these laboratories started catering to the needs of industries throughout India. Over last 5 decades, CMTI had significantly contributed in Product development, Technology development, Training, Framing Standards, Development of Artefacts in Metrology field. CMTI has been a forerunner in all the above aspects in the country particularly in dimensional and surface metrology.

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N. Balashanmugam ¹, K. Ankit ¹, K. Niranjan Reddy ¹, V. Shanmugaraj ¹, P. V. Shashi Kumar ¹

Affiliations
1 Central Manufacturing Technology Institute, Bangalore, IN

Abstract

Productivity in manufacture of high aspect ratio cylinders depends on how quickly the inspection parameters are measured and corrective actions are token. Long cylinders undergo a series of processes including bend removal and machining. These processes undergo a series of iterations consuming considerable amount of time for the measurement of straightness of cylinder. In this paper, a concept is proposed, where, the straightness of the bore of a cylinder (barrel) is measured in-situ on the machine. In this method, the barrel diameter and thickness are measured at number of planes using touch trigger probe and ultrasonic transducer respectively. Ultrasonic transducer assembly and the touch trigger probe are mounted on the turret of the CNC Turn Mill Centre. The setup for ultrasonic based measurement includes a nozzle for the supply of stream of liquid on the work piece, an ultrasonic transducer and a data capturing unit. Echo from ultrasonic waves is obtained back from the stream enabling the measurement of the relative position from the outer profile of the work piece to its internal profile. By orienting (rotating) the work piece at different locations in the same plane, thickness and diameters are measured. Straightness is measured by continuing to measure along the length of the cylinder. The thickness and diameters obtained are then used for the evaluation of straightness of the bore.

Keywords

Straightness, Cylinder, Touch Trigger Probe, Ultrasonic Transducer.

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N. Balashanmugam ¹, P. V. Shashikumar ¹

Affiliations
1 Micro Engg. and Nano Technology Division, Central Manufacturing Technology Institute, Tumkur Road, Bangalore-560022, IN

Abstract

Miracles are indeed happening around the world with the wide and continuously expanding applications of Laser. Pulsed lasers show its supremacy over continuous wave lasers in micro machining. Solution seems to be available to machine any material in nano metric range with laser. New lasing materials available in the present day are aiding this objective. Ultra short pulse lasers generate curiosity in the field of micro machining as its application area is rapidly increasing.

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A. Umesh Chandra ¹, N. Balashanmugam ¹, J. Thyagarajan ¹, G. Sudheendra ¹

Affiliations
1 Central Manufacturing Technology Institute, Bangalore, IN

Abstract

Resource allocation by clustering is an effective method of creation of manufacturing cells. This works in the Prototype manufacturing environment also. This paper presents methodology adopted for formation of manufacturing cells by Production Flow Analysis (PFA) using Rank Order Clustering (ROA) algorithm. The original layout and redesigned layout are analyzed for material flow using the software FactoryFlow. The results indicate substantial reduction in movement of material flow and realisation of benefits of cellular manufacturing. This paper also discusses the monitoring method adopted for tracking the components.

Keywords

Resource Allocation, Prototype Manufacturing, Cell Formation, Material Flow, Clustering.

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B. Dattatreya ¹, K. Anil Kumar ¹, R. Murali Krishna ¹, V. A. P. Sarma ¹, S. K. Verma ¹, S. Arumugasamy ¹, N. Balashanmugam ¹

Affiliations
1 Central Manufacturing Technology Institute (CMTI), Tumkur Road, Bengaluru, IN

Abstract

Lapping is one of the techniques where form and surface roughness are controlled on surface like flat, cylindrical and spherical shape. Now a days with optimized parameters and the process is being applied to any material and shape which are not subject to plastic deformation due to their own weight or to mechanical load by machining. It is used less for finish and more for form accuracy, such as flatness in the case of flat objects or sphericity in the case of spheres. The parameters optimization is key factor for lapping spherical surface. This paper gives brief about development of Sphere Lapping Attachment for CNC Lathe with Spherical tolerance accuracy within 1 micron for lapping spherical surface with scratch-free, mirror finish high-quality surface. This Attachment is effective on stainless steel and Cobalt Chrome (Co Cr) alloyed metals.

Keywords

Lapp Tool, Lapping Paste, Lapping Attachment, Surface Roughness, Surface Finish, Sphericity, Roundness, Form, Co Cr, etc.

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Sunil Magadum ¹, K. Niranjan Reddy ¹, M. Chellamalai ¹, N. Balashanmugam ¹

Affiliations
1 Central Manufacturing Technology Institute (CMTI), Bengaluru, Karnataka, IN

Abstract

Standard glass scale is just like a kind of very precise ruler and on its surface, accurate divisions are equally marked. The standard glass scales are frequently used in calibration of precise instruments with non contact method of measurements like optical microscopes, video microscopes, profile projectors etc. With the help of ultra fast pulsed laser micromachining system devised a state of the art process for manufacturing standard glass scales. The machined standard scales were calibrated using F25 CMM for 10 mm range scale and Profile projector for 150 mm range scale. The results of the calibration shows the accuracy of the Glass scales at par with the scales manufactured by photolithography process.

Keywords

Standard Glass Scale, Gratings, Stage Micrometers, Ultra Fast Pulsed Laser.

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K. Ankit ¹, K. Niranjan Reddy ¹, Gokul ², N. Balashanmugam ¹

Affiliations
1 Central Manufacturing Technology Institute (CMTI), Bengaluru, IN
2 National Institute of Technology Karnataka (NITK), Surathkal, IN

Abstract

Carbon Nano Tubes (CNTs) were deposited on Silicon substrate by RF plasma enhanced chemical vapour deposition (RF-PECVD). The deposition was carried out at 550 V bias and 600°C with C₂H₂ precursor gas diluted with H₂ in the ratio of 1:4. Transition metal catalysts are required for CNT growth by PECVD. It is believed that the catalyst on the substrate must be in the form of particles instead of smooth, continuous films. The eventual particle size and the resultant nanotube diameter correlates to film thickness. Thinner films in general lead to smaller particles and tube diameters. While a small grain size is not guaranteed in as-prepared films, steps are taken to break the film into desired particles to form island like structures. This work investigates the effect of Nucleation and the time interval of Nucleation on the CNT growth process.

Keywords

CNT, Nucleation, RF-PECVD

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B. N. Manjunath ¹, A. R. Vinod ¹, S. K. Verma ¹, N. Balashanmugam ¹

Affiliations
1 Central Manufacturing Technology Institute(CMTI), Tumkur road, Bengaluru, IN

Abstract

Additive manufacturing has changed the way products are designed, manufactured and distributed to the consumers. It has made possible to create products previously thought too complex. Aerospace, medical, automotive and energy sectors started using additive manufacturing as they realised its potential innovation, financial and efficiency benefits. Despite the progress, there are still challenges that must be addressed, including improving the throughput, Accuracy and repeatability, surface roughness, mechanical properties, establishing standards and protocols, modelling and simulation to reduce the residual stress, certification and reducing the raw material cost. This article gives insights into the present barriers hindering the widespread adoption and research opportunities in metal additive manufacturing.

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