Applied Mechanics and Materials Vols. 766-767

Abstract: Wind Turbine Industry is always seeking to improve and better its product options to its customers. One way of doing so is by bettering and optimizing its existing product offerings. The structural support component of a Wind Turbine Generator, which is approximately 15% of the total wind turbine cost and includes the tower and rotor yaw mechanism. It is possible to both discreetly increase the strength of the platforms and reduce its overall cost in terms of material costs by selecting suitable alternate material. The new platform is tested for stability under practical loading conditions by the Finite Element Analysis (FEA) using ANSYS software. The aim of the project is to minimize the cost and weight of the Service platform by 15-18% without compromising on its structural integrity interfaces.

Abstract: The paper presents the results of tensile behaviour, microhardness, surface roughness and microstructure of Ni-Cr alloy surface treated using high power Q-switched Nd: YAG laser has been studied. The major clinical disadvantage of the Ni – Cr is their lack of adequate ductility and yield strength. These properties combined made finishing, polishing and burnishing of conventional base metal alloys rather difficult. The dumbbell shaped tensile and cylindrical specimens of Ni-Cr were cast with a phosphate bonded investment material, using an induction melting centrifugal casting machine. The microhardness values of the surface melted layers increased as compared with Ni-Cr as - cast condition. The results of experiment showed that the surface treatment process has improved the % elongation, and surface roughness and microhardness as compared with as-cast. The improvement of the mechanical properties may be attributed due to grain refinement imparted by laser shock peening. The microstructure and changes in crystal orientation presented in the surface layer of the laser treated material were analyzed by optical, SEM as well as XRD. The chemical composition of laser treated surface was determined by EDAX attached along with SEM. Vickers microhardness was measured as per ASTM E384 11el standard test method. The data were compared using ANOVA and post hoc –Tukey test. In our present study, the laser shock peening process shows, a substantial increase in surface roughness from Ra = 0.440 μm before LSP treatment to 1.781 μm and surface hardness of Ni-Cr was achieved by 53.5% the base material hardness (i.e. from284 HV to 436 HV) and the mean values of % elongation of Ni-Cr alloy was higher (double) than that of after laser shock peening. The mean values of UTS, YS, modulus of elasticity of Ni-Cr were significantly lower after LSP. The experimental results showed that the mean values of percentage elongation of Ni-Cr increased by 200 % after LSP. It is evident from the above experimentation, increase of ductility of Ni-Cr alloy facilities workability which could produce a reliable removable partial denture (RPD) metal framework for dental prostheses.

Abstract: Ceramic coating on the internal combustion engine has appeared as one of the great means that increase performance and efficiency of an engine. This paper presents a novel approach for the optimization and study of the effect of performance of ceramic coated internal combustion engine. In this paper, different parameters like engine load and engine speed are optimized with the consideration of various responses such as engine power output, volumetric efficiency, heat transfer rate to coolant and carbon monoxide (CO) emission. Experiments are carried out by varying the parameters of load and engine speed of ceramic coated internal combustion engine. Orthogonal array is taken to conduct the experiments with the load of 40 Nm, 120 Nm, 200 Nm and speed of 1200, 2000 and 2800 in rev/min. This method shows a good convergence with the experimental and optimum process parameters where maximum volumetric efficiency, minimum heat transfer rate and minimum CO emission are obtained by using the grey relational analysis method.

Abstract: The objective of the paper is to investigate the formation of Bio-fuel from waste plastic scrap. The experiment was carried out by converting the waste plastic into useful alternative oil by means of pyrolysis process. Main component of working model were furnace as heating coil and condenser as cooling coil tube. The arrangements have made to continue the process constantly. The waste plastics have kept in furnace. The furnace having heating coils which provides required heat to melt the waste plastics by three phase electric supply. Due to the high temperature in furnace waste plastics have been melted and liquefied at 350°C and formed as a vapour at 450° C. Then these vapours were sent to condenser which cools from heated vapour into liquefied oil by cooling process with slow down temperature of 30°C to 35°C. Here the vapour is fully consisting of gaseous hydrocarbons property. These hydro carbons can be used as a bio fuel after the condensation. The fuel properties were tested in reputed laboratory testing centre.

Abstract: In this present paper, an attempt has been made to examine the performance and emission characteristics of a single cylinder diesel engine fueled with blends of mixed biodiesel (Thevetia peruviana, Neem, Jatropha, Pongamia). Experiments were conducted with various blends of mixed biodiesel in CI engine for different loads. The results show that lower brake thermal efficiency and higher brake specific fuel consumption were obtained with mixed biodiesel blends when compared with diesel. Lower the value of CO and HC and higher the value of CO₂ emissions were determined for mixed biodiesel blends compared to that of diesel. Also, higher in NO_x and lower smoke opacity were found compared to diesel.

Abstract: The present investigation focuses on the influence of failure of material during maintenance of aeroengines installed in helicopters. This research study is on fifty eight engines withdrawn prematurely over a period of five years from the helicopters operated around the country before the completion of their actual life periods due to the failures of materials as serious defects. The effect of the trend of these defects was investigated thoroughly based on the analysis reports on the observation from the stripping laboratory test and the study on the investigation done thereafter at the defect investigation agency of the engine at overhaul shop. The entire study of these defects is carried out from the facts received from the analytical and experimental investigations. The remedial measures are identified and established after a deep evaluation. The causes of the factors attributing to the development of defects are found out by research analysis. They are mainly based on design, qualities of material, poor standard in quality control procedures and maintenance practices. They are implemented by the users for the achievement of reduction in the occurrence of such defects towards a significant improvement in the subsequent maintenance of aeroengines. Further, the remedial measures, besides prevention of occurrence of such defects has a great impact on the development of a high degree of aeroengine maintenance The final results of this research study are prepared as suggested measures to be forwarded for implementation to manufactures, overhaul agency and operators

Abstract: There are several methods to improve surface characteristics. Detonation Gun coating (D-Spray) is one of the popular method in thermal spray coating technique. Generally, to enhance the surface properties like wear and corrosion resistance, microhardness, surface finish etc.. D-Spray process was preferred. In this present study, the property of surface finish was considered for the coating powders of WC 14Co and WC 14Co+CNT. The Powder WC 14Co+CNT was prepared in a systematic way and coating process was carried out by using detonation gun coating technique. Scanning Electron Microscopy (SEM) had been done on the powders of with and without CNT and Atomic force Microscopy (AFM) analysis on the surface was done for various places on the surface. A significant effect on the surface finish was exhibited.

Abstract: A relative study among various types of coating materials to develop wear resistance of stainless steel has been performed. Ceramic coatings with the thickness up to 250 μm were prepared by Atmospheric plasma spray technique on the stainless steel. Two different types of coating materials such that Yttria Stabilised Zirconia, Zirconia Ceria powder were used. The influence of Ceria powder on abrasive wear was determined. It was found that the addition of Ceria to Yttria Stabilised Zirconia in a sufficient amount helped in increasing its wear resistance compared to the wear behaviour of pure Yttria Stabilised Zirconia powder. Moreover, it was found that the lesser the surface roughness of the coating layer,.

Abstract: The wear and corrosion resistance of working surfaces can be improved by applying suitable coatings using thermal spray techniques. In the present work air plasma spray deposition technique (PSD) was used to coat Al₂O₃ ceramic powder on AISI 410 grade stainless steel. The steel substrate was primarily coated with Ni/Cr which acts as a bond coat for good fastening. Surface morphology of Al₂O₃ particulates of the coating was examined by scanning electron microscope (SEM). Uniform distribution of the Al₂O₃ particles on Ni/Cr pre-coated steel substrate was observed. Sliding wear tests under dry condition were conducted for different sliding velocity by keeping applied normal load and sliding distance constant. The results indicate significant improvement in the wear resistance of Al₂O₃ coated stainless steel substrate using PSD. The micro hardness of Al₂O₃ coated surface was found to be higher than that of the base metal.

Abstract: Coatings are applied for protection of mild steel against corrosion. The paper deals at development of TiO₂ coatings onto mild steel substrate by Atmospheric plasma spraying. The coating thickness was taken as 250μm. Surface characterization was analysed by Scanning Electron Microscope. The surface roughness was determined by Atomic Force Microscope. The average roughness was found to be 459.009 nm.