The basic idea of 3D-printing is as simple as it is ingenious. In traditional 2D-printning, a computer code is used to print a two-dimensional picture with ink on paper. In 3D-printing, other materials are used, for example plastic or metal, and the printing is made in layers on top of each other, thus building three-dimensional structures.
In his PhD-project, Didunoluwa Obilanade is studying a printing method called Laser Powder Bed Fusion (LPBF) in which a laser beam is used to melt metal powder. Thanks to the small spot size of the laser beam, it is possible to make very intricate features and structures often found in products within the aerospace industry.
Reduce surface roughness
However, the technique also has limitations. For example, the higher the build angle of a structure being printed in relation to the plate it is built on, the higher the superfluous effect of the laser beam with the metal powder. This results in partially melted powder to form on the part, causing a rougher surface and with that potential areas for cracks and stresses. To reduce such surface roughness, support structures can be used. Hence, post processing is needed to remove surface roughness and the added supports. However, building support structures require extra material, and additional post processing is time consuming.
This is where Didunoluwa Obilanade’s research project will be put to use. His aim is to look at how engineering design methods can help solve AM problems such as surface roughness, thus enhancing the performance and reducing time to market for aerospace components.
“I have been interested in additive manufacturing for a long time. Compared with traditional methods it can be so much faster and there are also many more design possibilities. Further there are both economic and environmental gains to be made since, theoretically, you can use almost the exact amount of material needed in additive manufacturing without wasting any” says Didunoluwa Obilanade.
In his project he will interview engineers in the aerospace industry to get a better understanding of the requirements needed to develop an effective design method for 3D-printed aerospace components. Furthermore he will use the equipment at Luleå University of Technology to make and evaluate small test prototypes. The aim is to provide engineers with a validated framework for AM design. It is a continuation of research conducted by Christo Dordlofva, PhD at Luleå University of Technology. Christo Dordlofva will also be involved in the current project.
I’ve always wanted to do a PhD since I wrote my master thesis about additive manufacturing of large-scale spacecraft structures and since I have a background as an aerospace engineer, this project was the perfect fit, says Didunoluwa Obilanade.