About
Ayesha Sharif
Postgraduate Researcher
Ayesha Sharif is a PhD researcher based in NUI Galway. She obtained her bachelor’s degree in physics from Lahore College for Women University, Lahore Pakistan. She then joined the Centre for Advanced Studies in Physics, Government College University, Lahore Pakistan and acquired an MPhil in applied physics. During her master’s, she worked on laser matter interaction, laser induced plasma and laser induced breakdown spectroscopy.
Research Interests (Lay Summary)
Ayesha began her PhD with I-Form in February 2019. Her main research interests are laser matter interaction, ultrashort laser sintering of nanoparticle inks and process optimisation. She is currently working on ultrashort laser additive manufacturing and the optimisation of metallic microstructures in laser additive manufacturing.
Technical Summary
The residual porosity (defects) created during conventional long pulse laser sintering significantly alters the properties of the manufactured part and results in surface imperfections. Also, the heat-affected zone is impacted, resulting in the formation of pores, voids and cracks.
The aim of this research is to improve structural properties and crystallinity by controlling the growth of the defects. The solution is to use nanoparticle inks instead of bulk material to create functional and precise surfaces with closely spaced nanoparticles by avoiding pore formation. Most importantly, employing ultrashort lasers (femtosecond and picosecond) for sintering of nanoparticle inks for rapid energy transfer to avoid thermal damage. The research involves an in-depth investigation of low temperature melting of nanoparticles with ultrashort lasers, electron/lattice temperature and an optimisation of processing parameters, e.g. laser fluence, wavelength, pulse duration, repetition rate and laser scan speed.