Biodegradable implants in porous iron obtained by additive manufacturing
01 January 2022 Project SheetINEGI's Contribution
- Gather the information required to define the systems to study to obtain the desired behaviour.
- Define the standards and protocols of the tests to be performed.
- Characterize the bulk iron material properties through tensile, compression and bending tests with a digital image correlation (DIC) system, and characterize the iron powder microstructure.
- Select and design lattice structures with different unit cell shapes with a graded structure to simulate the human bone.
- Characterize the mechanical behaviour of the graded and non-graded lattice structures by finite element modelling and to identify the iron lattice structures with mechanical properties similar to the human bone.
- Select and optimize the parameters of the additive manufacturing process.
- Define the manufacturing protocols for sample fabrication.
- Prepare the iron materials considering different powder characteristics.
- Manufacture the samples previously designed.
- Evaluate the biocompatibility of the lattice graded iron biomaterial in standardized cells.
- Evaluate the ability of most clinically important bacteria to form biofilm in the lattice graded iron scaffolds.
- Predict the systems’ potential for prototype development and clinical application, based on the biocompatibility results.
- Disseminate the project results.
- Apply the concept and construction design that had the best performance in the lattice structures for mechanical bone-joining elements.
- Develop a prototype for a possible clinical application.
- Validate the global concept and evaluate its suitability for patenting.
- Register a patent covering the invention characteristics, if the previous objective is fulfilled.
Results/Impact
- Definition of the non-graded lattice structures with adequate properties. Extensive design selection combined with a finite element modelling will allow the right lattice selection.
- Manufacturing protocols defined based on the optimization of the process parameters which will be the most adequate to produce the iron samples by SLM.
- Graded lattice structures that conduct mechanical properties similar to the human bone selected using the appropriate design, which were evaluated by FEM.
- Extensive characterization of relevant structural and mechanical properties of the iron lattices suitable for the intended application. Iron lattices with adequate characteristics for other tests. A workshop on additive manufacturing of metals, to disseminate the experience achieved.
- Extensive characterization of the biodegradation and biocompatibility to conclude about the suitability of the iron lattice structures to be used as temporary implants. The biodegradation rate and biocompatibility quantified for the graded and non-graded lattices studied.
- Global analysis of the results to conclude about the development of a temporary implant based on iron lattice structures. Final seminar, open to the material sciences, mechanical engineering, and microbiology community, as well as industrial stakeholders, to present the analysis of the results and to define new research lines.