Executive Summary : | The gas turbine manufacturing industry has evolved over the past few decades in improving fuel economy through high engine efficiency by incorporating alterations in design and manufacturing technologies. Especially the manufacture of engine components such as compressor blades and the disc play a vital role in improving the efficiency. To improve the efficiency and reduce the weight of the engine there is need for lightweight composite structures. Different processes such as Adhesive bonding, Physical Vapour Deposition (PVD) Chemical Vapour Deposition (CVD) and some spraying coating techniques are being used to manufacture these structures. These above processes involve high utilization of consumables and these processes involve multiprocessing requirements to produce the desired composite components. Even though the conventional processes produce very good joints with high bond efficiency when compared to the base materials in terms of weight and strength, they are not capable of retaining the properties at very high temperature environments. Also, the conventional processes available for successful fabrication of Ti alloys is very scant due to its high reactivity when the temperature is elevated. Thus, there is a need for advanced joining techniques such as solid-state vacuum diffusion bonding (DB) for fabricating Titanium components. Vacuum diffusion bonding is a solid-state welding technique widely used for joining similar and dissimilar materials and it eliminates the formation of brittle intermetallic phases in the joint region and an eco-friendly process when compared to the other fusion joining processes. Reducing the overall weight of the engine component has become the most challenging task for researchers. It is believed and demonstrated by many researchers that the weight can be reduced by the production of composite structures. The composite structures will have a mixture of both metals and non-metals such as polymers, fibres etc. The incorporation of carbon fibres into any metallic structure is an advantage for both strength enhancement and weight reduction. Thus, in this applied research proposal, the efforts are aimed to reduce the weight of the titanium blade-ring component, which aids in improving the efficiency of the gas turbine engine. The weight reduction will be achieved by joining stacks of Ti6Al4V wires (0.25mm diameter) with and without fibre reinforcement by the vacuum diffusion bonding process. The effect of process parameters on the mechanical properties and microstructures will be evaluated. The hightemperature properties of the DB’ed composite stacks (Titanium ring) will be evaluated based on their application ranges. The performance of the component will be modelled and simulated through Finite element analysis and validated with the experiments. |