The present experimental analysis has been carried out to compare the changes in the tribological and mechanical properties of brass samples with and without heat treatment. Four Cu-Zn alloy samples are heated in various temperature ranges between 350°C to 800°C. Changes in hardness of all samples are recorded to observe the effect of temperature and time duration. Wear tests are performed in both dry and lubricated conditions. Wear loss and coefficient of friction of samples were measured at loads 20 N, 30 N, 40 N, and 50 N and at rotating disc speeds of 120 rpm, 140 rpm, 160 rpm, and 180 rpm at fixed track diameter for 8 minutes. Better tribological performance was found in the lubricating condition within the entire range of tests carried out. Minimum wear rate was observed for the samples heat treated at 650°C. The wear behavior is also investigated for both kind of samples. Deep grooving and micro ploughing phenomena are observed for non-heat-treated specimens. In the heat-treated state, the plasticity formation is more prominent.

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Gas turbine play an important role in producing power for aviation industries. A sustainable operating life with high efficiency of a gas turbine requires very high temperature operation. The increase in thermal conductivity with temperature results in high thermal stress which leads to permanent deformation reducing blade life and efficiency. A thermal barrier coating is crucial to remove such detrimental effects. In the present work, an assessment of gas turbine blade materials has been carried out to study the effect of various coating techniques to improve longevity of blades. Coating methods have been found to play an important role in determining the sustainability of gas turbine performance. It was revealed that such coatings considerably reduce the heat penetration rate and thus increase the service life of gas turbine blades.