Conference Papers

Permanent URI for this collectionhttps://idr.nitk.ac.in/handle/123456789/28506

Browse

Filters

2017 - 201942020 - 20241

Settings

Author: search.filters.author.Shivananda Nayaka, H.

Search Results

Now showing 1 - 5 of 5
  • No Thumbnail Available
    Item
    Microstructure and mechanical properties of magnesium alloy processed by equal channel angular pressing (ECAP)
    (Elsevier Ltd, 2017) Gopi, K.R.; Shivananda Nayaka, H.
    Equal Channel Angular Pressing (ECAP) with different passes was carried out for Mg-Al-Mn (AM) series magnesium alloy to investigate the microstructure and mechanical properties. ECAP process was carried up to 4 passes using route BC, where the samples are rotated by 90° in the same direction between consecutive passes. Microstructures were studied using optical microscope (OM) and scanning electron microscope (SEM) and it was observed that the grain size was reduced from 100 μm to 1 μm after 4 passes. Tensile test was conducted and the ultimate tensile strength (UTS) increased up to 2 passes but decreased with higher passes, even though grain size became finer with increase in ECAP passes. Microhardness was carried out and it was observed that the hardness was increased up to 2 passes of ECAP and decreased with higher passes. © 2017 Elsevier Ltd.
  • No Thumbnail Available
    Item
    Development, Characterization, Mechanical and Corrosion Behaviour Investigation of Multi-direction Forged Mg–Zn Alloy
    (Springer International Publishing, 2019) Anne, G.; Ramesh, S.; Kumar, G.; Sahu, S.; Ramesh, M.R.; Shivananda Nayaka, H.; Arya, S.
    In the present study, homogenized Mg−4%Zn (wt%) alloy was exposed to multi-direction forging (MDF) at 280 °C up to 5 passes successfully. Microstructural evolution, mechanical properties and corrosion behavior of the MDF-processed Mg−4%Zn alloy was investigated using different characterization techniques. Five passes of MDF (cumulative strain, ΣΔε = 3.45) led to the formation of ultrafine grain structure (grain size ~2.3 μm) with high angle grain boundaries (HAGBs) and high dislocation density. Corresponding ultimate tensile strength (UTS) and microhardness were observed to be 228 MPa and 88 Hv. Potentiodynamic polarization test results exhibited higher corrosion resistance (0.38 mm/y) in comparison with that of homogenized condition (1.33 mm/y). © 2019, The Minerals, Metals & Materials Society.
  • No Thumbnail Available
    Item
    Electrochemical Behaviour of ECAP-Processed AM Series Magnesium Alloy
    (Springer International Publishing, 2019) Gopi, K.R.; Shivananda Nayaka, H.
    Equal channel angular pressing (ECAP) is a technique for inducing high strain into the material to achieve ultrafine grain refinement. AM80 magnesium was processed by ECAP with processing route BC. ECAP-processed samples were tested for microstructural studies and electrochemical measurements. Potentiodynamic polarization test revealed decrease in corrosion current density due to uniform refined microstructure of the processed samples. Increment in charge transfer resistance (Rt) was observed for ECAPed samples with increase in capacitive arc diameters in Nyquist plots showing increased corrosion resistance in comparison with as-cast condition. The increment in corrosion resistance is because of grain refinement and uniform dispersal of intermetallic particles, which improved development of protective layer and bonding due to increased grain boundary density by ECAP process. © 2019, The Minerals, Metals & Materials Society.
  • No Thumbnail Available
    Item
    Effect of multiaxial cryoforging on wear properties of cu-1.5%ti alloy
    (Trans Tech Publications Ltd ttp@transtec.ch, 2019) Ramesh, S.; Shivananda Nayaka, H.
    Copper-Titanium alloy was subjected to multi axial forging (MAF) at cryogenic temperature. Microstructure evolution was observed using optical microscope (OM). After 9 pass of MAF, grain size reduced to 2 µm. As number of MAF pass increases, hardness of the sample increased, due to strain hardening effect. Dry sliding wear test was performed on as-received and MAF processed samples using pin on disc wear machine. Tests were performed at 30 N and 40 N loads at 3 m/s constant speed and at 1000 m and 2000 m, sliding distance. Scanning Electron Microscope (SEM) and EDS was used to analyze the worn-out surface of the specimen. Wear mass loss of MAF processed sample reduced, with increased number of MAF passes. Frictional Coefficient (COF) reduced with increase in MAF passes and improved with increase in load, because of increase in contact area between sample and disc. © 2019 Trans Tech Publications Ltd, Switzerland.
  • No Thumbnail Available
    Item
    Development of a Rack-and-Pinion Mechanism with Arduino-Based PID Control System for a Continuous Passive Motion Device in Knee Rehabilitation
    (Institute of Electrical and Electronics Engineers Inc., 2024) Sholapurkar, S.U.; Chanda, S.; Verma, K.; Shivananda Nayaka, H.; Das, B.
    This paper outlines the design and prototyping methodology for a simple, cost-effective device intended for Continuous Passive Motion (CPM) therapy, specifically for knee rehabilitation. The device is designed to assist patients in recovery by providing controlled, repetitive motion to the knee joint without requiring active participation. Its core mechanism utilizes a rack-and-pinion system, which converts rotational motion into linear motion, ensuring smooth and consistent lower limb movement. A PID controller has been implemented using an Arduino Mega microcontroller to provide precise control over the motion. This setup allows for accurate adjustments to both position and speed, aligning with the therapeutic requirements for effective rehabilitation. Key success factors and failure points are also highlighted, providing valuable insights for future improvements and development. © 2024 IEEE.