Now in her fourth year of study, Hayley says she has not only developed the practical skills to work on her Honours project, but also the knowledge to make an informed decision about what area of Engineer to specialise in. “Coming into my fourth year was pivotal because I wanted to do something related to material science. That subject is just amazing,” she says.
“With materials engineering, you're essentially working with a range of materials to optimise its use,” she says. Hayley is especially interested in the biomedical side of engineering, and has decided to work on improving bone scaffolds for her Honours thesis.
“Basically, I'm trying to optimise the geometry of an artificial scaffold that may have to replace a human bone. I am aiming to enhance permeability, which is how well fluid flows through porous media,” she says. “Bones need to receive nutrients and oxygen, for instance.”
Doctors will sometimes transplant fragments of other bones, such as a jawbone. But these bones have different mechanical properties and might not always be the best choice for the patient. This is why ceramic or metal may be used to engineer artificial bones for a patient.
Hayley has decided to work with ceramics as she finds they are more versatile than metal. “With ceramics, you can have bioactive or bioinert variants,” she says. “When you are using a bioinert material, your body will grow over the material. When using a bioactive material, your body can ‘consume’ this bone. The difference is that the bioactive material stimulates biological activity whereas other one does not, so harmful effects may not occur.”
Hayley is especially interested in femurs (thigh bones) and tibias (shinbones). She uses a software called Ansys, an engineering simulation and 3D design program, for work such as compression testing, which tests the strength of the bone. “I'm also trying to optimise the flow through the bone,” she says, “as well as testing the effect of different bone curvatures on how cells adhere to the different areas.”
When Hayley presents her final results at her Honours presentation, Hayley is planning to display the final product not only on a computer screen, but also as a small replica. JCU just got a 3D ceramic printer, so we are actually able to print our models and clean them. We do all these processes ourselves before we have our final product, rather than sending our designs off to a company and waiting ages,” she says, adding that this allowed her to gain valuable practical experience.