Research Projects

Most aerospace fuselage and engine components fail due to low oxidation, wear, corrosion, creep resistance, hydrogen embrittlement, fatigue failure, low strength at elevated temperatures, stress corrosion cracking, diffusion, and environmental degradation. Understanding these failure mechanisms is crucial for designing materials that can withstand harsh operating conditions and prevent unexpected failures. NiTi shape memory alloy (SMA) is used to manufacture these components, but they encounter issues, such as degradation of their shape memory and super-elastic properties at elevated temperatures, reduced high-temperature strength and fatigue strength, and oxidation and corrosion resistance. Efforts to enhance NiTi SMAs properties through elemental, but often result in reduced ductility or prohibitive costs, limiting their adoption in critical components High-entropy shape memory alloys (HESMAs) represent a transformative class of materials that address these limitations. Based on the high-entropy alloy (HEA) concept, HESMAs utilize multi-principal element strategies to achieve superior mechanical, thermal, and functional properties. These alloys exhibit excellent high-temperature strength, microstructural stability, corrosion and oxidation resistance, and enhanced phase transformation characteristics. However, some Fe-based HESMAs, despite their strength and corrosion resistance, still suffer from drawbacks such as high density, low oxidation resistance, and limited fatigue life. Fabricating HESMAs poses challenges due to their complex compositions, requiring precise microstructural control and its use for HESMAs remains limited. To address this, advanced computational techniques like CALPHAD and machine learning are being utilized to design and optimize alloy compositions and predict phase stability. Rapid tooling is a well-established manufacturing technique used for developing high-performance alloys under a controlled vacuum atmosphere. This technique integrates 3D printing (Additive Manufacturing) and ultrasonic-assisted pressureless sintering (UAPS) used to fabricate free-form components at a low cost. Rapid tooling provides high heating and cooling rates, leading to refined microstructures and improved mechanical properties. It is more energy-efficient than conventional methods and provides uniform heating, reducing defects such as particle cracking and void formation. Its ability to process materials with high melting points and strong affinity for oxygen makes it a preferred method in the aerospace and nuclear applications. This research proposes the development of novel HESMAs using in-house developed rapid tooling processes, with an emphasis on understanding their phase transformation behavior and properties. The outcomes are expected to contribute significantly to the development of next-generation aerospace materials and foster broader adoption of rapid tooling technologies in manufacturing sectors.