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NiCr metal is deposited on martensitic stainless steel using an atmospheric plasma spray method. To enrich the metallurgical properties of the NiCr metallic coating, a standard heat treatment process is adopted. From the investigation, it has been shown that the voids and porosity developed during the thermal spray have been controlled through heat treatment. Electron image analysis reveals that the coating has reduced porosity with strong and dense bonding strength. With reference to the surface hardness, the post-processed coating yields a maximum of 140 Hv compared with the coated (129 Hv) and base metal (115 Hv). Subsequently, the sliding wear behaviour of post-processed NiCr coating has a minimum wear of 25 μm for an applied load of 5 N and 57 μm for an applied load of 15 N. Owing to the high metallurgical bonding, the coating has sustained the heavy loads, and the wear formation is controlled. However, the base metal has an adhesive wear mechanism caused by the high frictional force on the sliding friction. Therefore, it is recommended that post-processed thermal barrier coatings possess good metallurgical bonding and withstand heavy load causing minimum wear.

In the present research work, Friction stir processing (FSP) technique has been applied to develop a C70600 graded copper-nickel (CuNi) Surface metal matrix composite (SMMC) reinforced with and without addition of ZrCp. Rotational and traverse speeds were set as 1200 rpm and 30 mm/min, respectively. The fabricated SMMC were metallurgically characterized by using Optical microscope (OM) and Field emission scanning electron microscope (FESEM). The homogeneous distribution of ZrC particles and good interfacial bonding between matrix/reinforcement were observed via OM and FESEM microscopes. The microhardness of the CuNi/ZrC surface composite was observed by using microhardness tester at the cross section of the sample. The average higher microhardness of 148 Hv at CuNi/ZrC SMMC and lower microhardness of 115 Hv at FSPed CuNi was found. The Ultimate tensile strength (UTS) value was measured by using micro tensile testing machine. The UTS value of CuNi/ZrC composite and FSPed CuNi were observed to be 310 MPa and 302 MPa, respectively. The mode of fracture was also observed via FESEM. The X-ray diffraction (XRD) test was carried out to confirm the presence of CuNi & ZrC in the SMMC layer.

The large-scale generation of electric power using solar energy stimulates the development of novel technologies by researchers with ultimate resource qualities. Solar energy collectors are the significant part of Solar Energy Thermal Power Plant (STP), which can be operated at a particular feasible range for utilizing the solar resource with its intermittent inputs. The life span of solar thermal power plant can be increased by designing the controller with a closed loop. The proposed hybrid design of solar plant involves a controller with closed loop transferring the solar energy to the heat transfer liquid, namely therminol oil, which acts as a medium for transferring heat in Parabolic Trough Collector (PTC) having single-phase flow. The concentrators are the parabolic reflectors focusing the rays on the line with a focal point using tracking mechanism having one axis. Solar collectors are utilized in the power converting technique of solar thermal energy, which concentrates sunlight for preparing Rankine cycle heat of high temperature. The steam turbine is driven by the superheated vapor using Rankine cycle with the shaft of the steam turbine connected to the generator for producing electricity. The life span of the Solar Energy Thermal Power Plant is enhanced as proposed design for solar collectors uses therminol oil as the heat transfer liquid. The controller design is implemented using Predictive Function Control (PFC) or Static Feed Forward (SFF) control with Proportional Integral Controller (PI) which provides the best performance with the added advantage of direct heat storage in the thermal plant. The simulated results are obtained for the proposed design of collector with the rate of change of variation and cost function of manipulated parameters, which are constant for the proposed controller but vary drastically for the conventional PI controller.