About
Dr
Muhannad
Obeidi
Funded Investigator
Dr Muhannad Obeidi is an Assistant Professor in the School of Mechanical and Manufacturing Engineering in Dublin City University. He obtained his degree in Mechanical Engineering from Baghdad University in 1988. He did his master’s degree and PhD at DCU in 2014 and 2018, respectively. He worked as a research assistant at the Advanced Processing Technology Centre (APT) in DCU from January 2015 till 2018 and as a post-doctoral researcher at I-Form Advanced Manufacturing Research Centre (DCU) from 2018. The research area was mainly focussed on Additive Manufacturing and metal 3D printing, the laser surface modification including texturing, polishing, hardening, sintering, and cladding.
Research Interests (Lay Summary)
Dr Muhannad has over 25 years of experience in Mechanical Engineering and metal processing. His current research focuses on the investigation and optimization of advanced manufacturing technologies including additive manufacturing (AM). The main processing parameters in the AM process of Powder Bed Fusion are the laser power, the scanning speed, the laser spot size and the build layer thickness, in addition to the initial powder particle size. The wide range in adjusting these input parameters, which is offered by 3D printers, leads to a wide variation in the resulting properties of the produced part. Such properties include mechanical, physical and chemical properties like the hardness, elastic modulus, final dimensions, porosity, surface roughness, phase change, grain size and colour. His research is being carried out on several metal powders, including 316L stainless steel, cobalt chromium, aluminium, and nitinol (NiTi) utilising different application in aerospace, automotive, tooling, and biomedical.
Technical Summary
It is important for manufacturers and AM users to understand the relationship between the laser input processing parameters and the output properties, which will help in the prediction of the part’s performance and life cycle. In order to achieve this aim, an experimental model must be modified in which a statistical description of this relationship can be established. Several instruments are necessary for characterization and measurement.
One of the main challenges in AM processing is the high heating and cooling rates and the differences/increase in the thermal energy between the later layers compared to the early build layers. Our AconityMini metal printer is fitted with a pre-heating element to mitigate this problem and to provide a better control on the heating/cooling rates. The extracted data is being tabulated and used for the optimisation and automation of the AM process.