Time filter

Source Type

Sunil B.R.,Rajiv Gandhi University | Reddy G.P.K.,Vignana Bharathi Institute of Technology | Patle H.,Visvesvaraya National Institute of Technology | Dumpala R.,Visvesvaraya National Institute of Technology
Journal of Magnesium and Alloys | Year: 2016

Surface metal matrix composites (MMCs) are a group of modern engineered materials where the surface of the material is modified by dispersing secondary phase in the form of particles or fibers and the core of the material experience no change in chemical composition and structure. The potential applications of the surface MMCs can be found in automotive, aerospace, biomedical and power industries. Recently, friction stir processing (FSP) technique has been gaining wide popularity in producing surface composites in solid state itself. Magnesium and its alloys being difficult to process metals also have been successfully processed by FSP to fabricate surface MMCs. The aim of the present paper is to provide a comprehensive summary of state-of-the-art in fabricating magnesium based composites by FSP. Influence of the secondary phase particles and grain refinement resulted from FSP on the properties of these composites is also discussed. © 2016. Source

Sampath B.S.,Vignana Bharathi Institute of Technology
URAI 2011 - 2011 8th International Conference on Ubiquitous Robots and Ambient Intelligence | Year: 2011

Automatic Fire Extinguisher Robot is a Hardware based model used to automatically extinguish the fire during fire accidents. A Robot has been developed which features to move in the direction with respect to the fire intensity. The Robot shield is coated with calcium silicate boards that are capable of withstanding very high temperatures. The principle used, was designed and experimented at a temperature of 300°C. The temperature sensing capability of the robot is varied by heating the Thermocouple ends to a cut-off temperature, above which the robot starts responding to the fire. The Robot finds its applications in Rescue operations during fire accidents where the possibility for service men to enter the fire prone areas is very less and also during wars to perform rescue functions. The most added advantage of this Robot is that it turns ON automatically as it detects the fire around its surroundings, using Thermocouple and tries to extinguish it by moving in the direction with respect to the fire. The temperature sensor provides a backup to the Thermocouple, if needed in vast circumstances. © 2011 IEEE. Source

Chandra Sekhar G.,Gmrinstitute Of Technology | Subramanyam P.S.,Vignana Bharathi Institute of Technology
World Journal of Modelling and Simulation | Year: 2016

Multiphase transmission system is a serious contender to the conventional Three Phase System. The fault analysis of Six Phase system is studied and adequate protection scheme is developed. A Logical protection scheme of Six Phase Transmission System against shunt and series faults using Logic Based Detection of negative sequence currents is presented in this paper. World First Six Phase Transmission Line is operating between McCalmont bus and Springdale bus of Allegheny Power System (APS),USA. A few amount of work had been reported on protection of Six Phase Transmission System in literature. This paper bridges the gap and paves the way to boost the research in Protection of Six Phase Transmission System. The Proposed Protection Scheme is a Novel approach as it doesn't require any special algorithms and using logical approach. Because of this the fault will be cleared with in one cycle and also the previous history of the healthy wave form just few cycle before occurrence of the fault can be traced for further investigation. The voltages and currents under fault for various types of fault had been taken from earlier studies of fault analysis of Six Phase Transmission line of Allegheny Power System. The proposed Logic based protection scheme is simulated to get a Logic 1 for fault conditions and Logic '0' for healthy conditions by using MATLAB/SIMULINK for shunt and series faults of both Unsymmetrical and Symmetrical faults on different phases of Six Phase Transmission system. Source

Saikrishna N.,Rajiv Gandhi University | Pradeep Kumar Reddy G.,Vignana Bharathi Institute of Technology | Munirathinam B.,Indian Institute of Technology Madras | Ratna Sunil B.,Rajiv Gandhi University
Journal of Magnesium and Alloys | Year: 2016

In the present study, AZ31 magnesium alloy sheets were processed by friction stir processing (FSP) to investigate the effect of the grain refinement and grain size distribution on the corrosion behavior. Grain refinement from a starting size of 16.4 ± 6.8 μm to 3.2 ± 1.2 μm was attained after FSP. Remarkably, bimodal grain size distribution was observed in the nugget zone with a combination of coarse (11.62 ± 8.4 μm) and fine grains (3.2 ± 1.2 μm). Due to the grain refinement, a slight improvement in the hardness was found in the nugget zone of FSPed AZ31. The bimodal grain size distribution in the stir zone showed pronounced influence on the corrosion rate of FSPed AZ31 as observed from the immersion and electrochemical tests. From the X-ray diffraction analysis, more amount of Mg(OH)2 was observed on FSPed AZ31 compared with the unprocessed AZ31. Polarization measurements demonstrated the higher corrosion current density for FSPed AZ31 (8.92 × 10-5A/cm2) compared with the unprocessed condition (2.90 × 10-5A/cm2) that can be attributed to the texture effect and large variations in the grain size which led to non-uniform galvanic intensities. © 2016. Source

Sunil B.R.,Rajiv Gandhi University | Ganesh K.V.,Rajiv Gandhi University | Pavan P.,Rajiv Gandhi University | Vadapalli G.,Rajiv Gandhi University | And 4 more authors.
Journal of Magnesium and Alloys | Year: 2016

Magnesium (Mg) and its alloys are now becoming the promising choice for various structural applications due to their low density and high specific strength compared with other light metals such as aluminum and its alloys. Among all Mg alloys, AZ (aluminum and zinc) series is the most widely used alloy system for various structural applications. But, machining of magnesium and its alloys involves certain issues due to their brittle nature and risk of inflammability unlike other nonferrous metals. Particularly, alloys with considerable amount of secondary phase may exhibit different machining characteristics during metal cutting operations. In the present study, two AZ series alloys AZ31 and AZ91 were selected and drilling operation was performed to assess the effect of the secondary phase amount and distribution on machining characteristics. Drilling operation was carried out at different sets of process parameters and cutting forces were obtained and the chips which have been produced during drilling were analyzed. From the results, it can be clearly understood that the presence of secondary phase (Mg17Al12) has a significant influence on cutting forces. Increase in cutting speed has reduced the required cutting force and load fluctuations in all the cases. © 2016. Source

Discover hidden collaborations