Additive Manufacturing (AM) of Ti-6Al-4V Lattice Materials– This fundamental research work focuses on the two-stage optimization of additively manufactured Ti-6Al-4V cellular materials, also known as lattice materials. The objective of this project is to study the effects of the various build parameters (build direction, scan strategy, etc.) during selective laser melting process on the microstructures and mechanical properties of Ti-6Al-4V alloy through various experimental methodologies, such as tensile testing, electron and optical microscopes, and X-ray diffraction.
Addition of Nano-particles during Additive Manufacturing of Aluminum Alloy-AlSi10Mg- One of the major problems associated with AM of metallic parts is the formation of columnar/directional grains that gives a significant mechanical anisotropy in the structural part. Columnar grains form due to the multiple melting and solidification cycles during AM process and also due to the lack of suitable nucleation sites, where new grains can form dynamically if the conditions are met. Addition of carefully chosen nano-particles (~1 vol%) during the AM process may work as nucleation sites by a mechanism called particle stimulated nucleation (PSN).
Fusion Welding of High Strength Aluminum Alloys- Aluminum alloys like 2024 and 7075 exhibit high strength and ductility but cannot currently be fusion welded. The major reason for this is that these high-performance engineering alloys contain large fraction of other alloying elements in order to produce complex strengthening phases during subsequent heat treatments. These same elements promote large solidification ranges, leading to hot tearing during solidification, an issue that has been difficult to surmount for many years. In this study, we are trying to incorporate various nanoparticles in the weld melt pool to stabilize the solidification range.
Linear Friction Welding of Dissimilar Titanium Alloys- In this project, we are investigating the dissimilar linear friction weldability of Ti-6Al-4V, the most common titanium alloy and Ti-6Al-2Sn-4Zr-2Mo, a titanium alloy used for high temperature applications in the aero-engine.
Effect of Heat Treatments on Microstructures and Mechanical Properties of Ti-5553 Alloy- Large aerospace industries like Airbus and Boeing have already started to use forged Ti-5553 (Ti-5Al-5Mo-5V-3Cr), a near beta titanium alloy for large landing gear components, it is a good time to start working on this alloy to further expand its use as wrought products. The properties of Ti-5553 are highly dependent on their internal microstructure, which often is composed of multiple phases and precipitates. The volume fraction, size, morphology, and distribution of these precipitates could significantly influence the physical and mechanical properties. Therefore, a complete and detailed understanding of phase transformation and microstructural evolution, is crucial in order to optimize the mechanical properties depending on various applications. For next few years, our plan is to understand the optimum processing parameters, processing defects, microstructures, precipitation kinetics, and associated mechanical properties of this alloy through various industrial and laboratory scale thermal and thermo-mechanical processing.
Optimized Surface Roughening by Pulsed Water Jet for Stronger Thermal Barrier Coating- When car engines fail, they are typically just taken out and replaced because traditional engine remanufacturing techniques can be excessively expensive. An innovative and new recycling technique has been developed that aims to give a new life to old engines that would otherwise be scrapped. The new process, which it calls Plasma Transferred Wire Arc (PTWA) coating technology, applies a spray to the inside of a worn-out engine block that helps restore it to its original factory condition. This project is investigating the formation of optimized surface roughness by using high pressure pulsed water jet technology. The quality of the PTWA coating will be studied by the microstructural characterization using optical and scanning electron microscopes to determine defects such as porosity, oxides, and unmelt particles. The strength of the coating i.e. the bond strength will be determined by pull-off tests.