Rajani K. Vijayaraghavan
Dr Rajani K Vijayaraghavan is a postdoctoral researcher working in the area of 3D printing process characterisation and metrology. She completed her PhD in materials physics, with a major focus on developing materials for energy and optoelectronic applications, at the School of Electronic Engineering, Dublin City University. She completed her master’s and bachelor’s degree in physics from University of Calicut, India. Her research interests lie primarily in the area of development of advanced functional materials/nanomaterials (including their synthesis, characterisation, surface engineering, mechanistic understanding and device fabrication) for energy, optoelectronic and biomedical applications. She has always been inspired by unique and unusual material behaviours and their origins and has been constantly interested in exploring them for a wide range of applications.
Research Interests (Lay Summary)
Dr Vijayaraghavan joined I-Form in August 2018 and since then she has been working in two areas: developing a sensing/characterisation method for additive manufacturing processes; and investigating the structure and properties of 3D printed materials/parts using a technique called X-ray diffraction. These two areas are key to ensuring process stability and product quality in the 3D printing process and to improving understanding of process mechanisms for future developments in this field.
The challenges of ensuring product quality, reliability, and process repeatability are key technological barriers that prevent widespread adoption of AM technologies in various manufacturing applications. These features are particularly important in high-value applications where parts failure cannot be tolerated. Development of suitable in-situ process monitoring methods are essential to improve AM parts quality and to address many of the challenges in AM processing.
During Selective Laser Melting (SLM), a plasma plume is typically produced above the melt pool and this plasma is likely to produce radio frequency (RF) electromagnetic radiations. One of the aims of this project is to characterise the additive manufacturing process by investigating RF emissions from the plasma plume using non-contact, non-invasive and in-situ RF monitoring tools.
This project also aims to correlate AM process characterisation data with post-process metrology using high resolution X-ray diffraction (XRD) techniques. Room temperature and temperature dependant XRD measurements will help to analyse properties/mechanisms such as microstructure evolution, phase transformation and micro strain in various printed parts.