[01] Ikpe Aniekan E., Department of Mechanical Engineering, Faculty of Engineering and Computing, Coventry University, West Midlands, UK.. [02] Owunna Ikechukwu, Department of Mechanical Engineering, Faculty of Engineering and Computing, Coventry University, West Midlands, UK.. [03] P. O. Ebunilo, Department of Mechanical Engineering, Engineering Faculty, University of Benin, Benin City, Nigeria. [04] Ememobong Ikpe, Department of Instrumentation and Control, Exxon Mobil Producing Nigeria, Ibeno, Nigeria.

Trade-offs are usually allowed during the material selection process of a given component, but the designer must have proper understanding of a component’s loading conditions, to be able to select materials with suitable properties that can eliminate or minimise failure during the duty cycle of such component. High strength-to-weight ratio is one of the most important requirements in the aerospace industries in terms of components performance. High Pressure (HP) compressor blades with a wide range of other parts in an aircraft engine require these properties for optimum performance. This is due to the in service condition (such as operation principles and the high temperature (450-600°C) environment of the HP compressor blade which subjects the component to Radial loads (caused by centrifugal forces acting on the blade) Bending Loads, Thermal Loads etc. thereby, inducing stresses, cracks and fractures (caused by compressor surging), fatigues and other material defects that can result in failure or limit the longevity of the blade. In this study, detailed material indices were derived for price, specific stiffness, yield strength, including fracture toughness, and a search was performed using CES software to determine the materials having the desired material indices. Since the material should be able to withstand the operating temperature of the HP compressor, a limiting factor of 500°C was set to filter off materials whose service temperature is below this value. Four materials passed the search including Low alloy steel, Nickel-based super alloys, Stainless steel and Titanium alloys. However, titanium alloys were found to meet the high strength to weight ratio at 500°C despite its high cost, while steel materials in this category had relatively high densities and some could not match up the temperature requirement. Above 500°C, more dense Nickel based super alloys were found to be preferable. Hence, Nickel based super alloys are suitable for applications requiring high performance at elevated temperature, but the high density might limit its suitability during material selection.

Compressor Blade, Material, Temperature, High Strength, Low Density, Loading Condition

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