Department of Mechanical engineering
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Item Monitoring of Fracture Healing Process by Acousto-Ultrasonic Technique Sharad Shrivastava1*(Universiti Putra Malaysia Press, 2019) Shrivastava, SharadPresently the radiological examination is widely used for the assessment of in vivo bone condition. In some clinical problems such as diagnosis of the point of union of a fracture; the manual assessment is used along with radiological examination. Uncertainty regarding the significance of the radiographic and clinical findings may result in unnecessary long immobilization periods which can produce discomfort for the patient, as well as possible stiffness of the joints and sometimes permanent loss of mobility specially in older population. This paper deals with the in vivo analysis of bones by Acousto-Ultrasonic technique. The fracture was created through surgery on one of the limbs of rabbit and healing process was monitored through acousto-ultrasonic technique. A new index known as bone healing index was defined to calculate the end point of healing. In most of the cases, the bone healing index value was found to be 0.80, indicating that 80 % of the strength could only be restored at the completion of healing process.Item The Micro Structure and Tribological Properties of Liquid-Fuel HVOF Sprayed Fine Wc-Co-Cr Coating(ASM International, 2015-05) Shrivastava, SharadThis study compares high-velocity oxygen fuel spray MJP5000 and MJP 6000 (Patented by Metallizing Equipment Company Pvt Ltd.) using powder WC-Co- Cr. The microstructure and phase composition of powders and coatings will be analyzed by scanning electron microscopy and X-ray diffraction. Coatings were also characterized by their hardness, bond strength, roughness, deposition efficiency. Therefore, coating of high hardness and wear resistance can be produced with all HVOF spray system when the proper spray powder and process parameters are chosen. The results demonstrate that the powder exhibit various phase transformation during the spray process depending on type of powder, spray system and spray parameters.Item Modification in Powder Feeder for Nano-Powder for Thermal Spray Thin Coatings(ASM International, 2016-05) Shrivastava, SharadThis paper discusses the modification of powder feeders to facilitate the deposition of nano materials by thermal spraying without the use of a suspension or solution precursor. Two powder feeder designs were developed and used to deposit nanocarbide coatings by HVOF spraying. The nano coatings were examined and tested, and the results are presented and discussed.Item In vitro study of bone condition using acousto-ultrasonic technique(Inder Science, 2011-04) Shrivastava, SharadThis paper deals with the in vitro analysis of bones by acousto-ultrasonic technique. The comparison has been made between normal bones and fractured bones. The significant difference between the Stress Wave Factor (SWF) of the two suggests that this technique can be used for monitoring the fracture healing process and various other bone abnormalities. The good correlation between SWF and the failure strength of the dry bone (R = 0.99) also indicates that this technique can also be applied to predict the mechanical integrity of bone. The good correlation between SWF and depth of crack indicates that the technique can also be used to measure the severity of the crack.Item Synthesis and characterization of fire resistance polymeric coating solution for carbon-blended aluminized (E-glass-based) and non-aluminized fabric(Taylor & Francis, 2019-05) Shrivastava, SharadIn this study, we report the development and characterization of fire-resistant non-intumescent polymeric resin for aluminized (E-glass-based) and non-aluminized (basofil/nomex/carbon-based) firefighting suit fabrics. The prospective coating resin is synthesized via two-step polymerization of polyimide using dimethylacetamide (DMAc) as a common solvent. 3-Aminopropyltriethoxysilane (APTES) is used as a coupling agent and is added just before coating. All the coating samples are prepared by hand layup technique and are allowed to cure (known as imidization) under the oven with increasing the temperature step-by-step from 80 to 350 °C. The imidization of coating resin is confirmed by FT-IR spectra analysis. Furthermore, all the samples are characterized with flammability, adhesion, thermal protective index, heat char and ignition, and thermal shrinkage as per BS 3120, MIL-C-29143, BS 3791, D-5537, and NFPA 1976 standards, respectively. The observed results confirmed that the prospective resin could be a better choice as fire-resistant coating for carbon-blended aluminized and/ non-aluminized fabric.Item CAD modeling and finite elemental design of indigenous knee brace(Springer, 2019-01) Shrivastava, SharadWalking problems aggravate with the advent of old age. One of the treatments for the walking problems is the use of knee brace. This paper reviews the existing designs of knee braces, assesses their merits and demerits and proposes an efficient, cost-effective, light-weight and attractive design of knee brace for Indian population. This paper models design of knee brace and analyzes stress shielding capacity of the knee brace using Finite elemental analysis. This paper discusses how this knee brace can overcome difficulties faced by other knee braces in market.Item Study of fracture toughness and bend test morphologies of HVOF sprayed Cr3C2-25% NiCr coating after heat treatment(IOP, 2017) Shrivastava, SharadMajority of the industrial components are subjected to high temperature exposure, where crack propagation occurs due to shear failure. The paper involves the study of the fracture toughness of heat treated Cr3C2-NiCr coating at three different service temperatures (750°C, 850°C, and 950°C for 1-hour aging) using indentation techniques to measure the crack resistance of the coating. At 750°C and 850°C, the coating cracked at the bend area, but not spalled. At 950°C, the coating spalled and delaminated from the substrate indicating poor adhesion after prolonged exposure. The influence of heat treatment on the fracture toughness and adhesion properties of the Cr3C2-25%NiCr coating were also investigated. The high temperature exposure at 950°C, resulted in a shear failure of the coating due to the presence of splat contraction. The increase in temperature increases the fracture toughness KIC of the coating, with the decrease in hardness. It was observed that the oxidation levels enhanced on the top layer of the coating, which acted like a core region for crack initiation at 950°C resulting in shear failure during bend test.Item Future research directions with Acoustic Emission and Acousto–Ultrasonic technique(Inderscience, 2015) Shrivastava, SharadThe paper deals with the existing research gap in medical field by the application of non-destructive testing technique. The paper gives an general idea about the various non-destructive testing techniques used in Biomedical field. It also covers the disadvantages of various techniques and how these disadvantages can be taken care by Acoustic emission and Acousto–ultrasonic technique. Based on literature review the gaps have been identified for the future research by these techniques. The assessment of bone condition can be effectively done by using acoustic emission and acousto–ultrasonic technique. Acousto–ultrasonic technique has already proved its usefulness in the assessing the composite materials. As bone is also a composite material, definitely this technique might give good results while assessing the bone condition.Item Effect of electroless Ni plating on the properties of cold-sprayed Ni–Al2O3 coatings(Emerald, 2017-06) Shrivastava, SharadThis study investigated the effect of electroless nickel (Ni) plating (Np) on the properties of cold-sprayed nickel–alumina (Al2O3) coatings. To develop this two-layered coating system, nickel–alumina powder coating was first deposited by the cold spraying method on a mild steel substrate. Then, electroless Np was deposited on the as-sprayed nickel–alumina coating. The coating properties of the as-sprayed nickel–alumina coating and of the two-layered Np/nickel–alumina system were critically examined. The microstructural evolution was analysed by scanning electron microscopy and energy-dispersive X-ray spectroscopy. In order to study possible changes in the mechanical properties of the system, Vickers microhardness experiments on the coatings and on the cross-sections were conducted. A possible improvement in the microhardness (14%) of the system was found after Np. Further, the corrosion behavior of the coating system was also studied critically. It was observed that the corrosion resistance of the Np/nickel–alumina coating system significantly improved and no corrosion effects and crack generation were observed at the substrate–coating interfaceItem Investigating the Effect of Cutting Parameters on Average Surface Roughness and Material Removal Rate during Turning of Metal Matrix Composite Using Response Surface Methodology(IJRITCC, 2015) Shrivastava, SharadThis research work investigate the effect of cutting parameters on average surface roughness and material removal rate during turning of Metal Matrix Composite using response surface methodology. The experimental studies are carried out under changing machining parameters like cutting speed, feed and depth of cut during turning of metal matrix composite. Response surface methodology based on the Face centered design technique has been used for the development of mathematical models to predict average surface roughness and metal removal rate. The conclusions revealed that the feed is the most influential machining parameter on the average surface roughness followed by depth of cut and the cutting speed. The depth of cut has significant for both the average surface roughness and metal removal rate for the MMC steel.