Speakers

As we prepare for Industry 4.0, there is a need for manufacturers to adopt new innovative technologies such as additive manufacturing (AM) or 3D printing for them to remain competitive. With AM, there is a shift in the manufacturing paradigm. Scientists and engineers can now conceive products that are previously hard to achieve using this evolving technology. However, one of the key challenges faced by AM today is the limited materials available for metal AM. In this seminar, two approaches, namely in-situ alloying and multi-metals processing, that are targeted to address this challenge will be presented.

Majority of the traditional materials used in conventional manufacturing are not designed or optimised for AM. A novel approach, known as in-situ alloying, is used to expand the library of available materials. Rapid modification of alloy compositions is made possible through design of experiments. Due to the peculiar powder-metallurgy and characteristics of AM, investigation of alloys that are previously inaccessible is now possible. It is found that the microstructure evolution of alloys formed in-situ is influenced by the dislocation and grain boundaries through diffusion enhancement which facilitates heterogeneous nucleation. Moving forward, the porosity-segregation dilemma observed in this approached need to be solved in order to achieve improved mechanical and physical properties.

Multi-metals processing remains another challenge for metal AM, especially for the powder bed fusion processes due to a lack of understanding at the interface between two discretely different metals. The functionality of components can be greatly increased by AM if they can have the properties of two or more discrete metals or alloys. Novel processing strategies have been developed to locally control the constitution, morphology, dispersion and transformation behaviour at the interface after understanding the interfacial properties. This allows prediction and modification of compatibility of multi-metals processing through metal AM.

Looking into the future, a “plug and play” approach to metal AM can be made possible through the understanding of fundamental sciences related to the processes, properties and performances of AM metals. In recent years, many numerical approaches have been developed to make reliable predictions by process parameter modifications. To fully realise the potential of in-situ alloying and multi-metals processing, there is need to synergise between simulations and experiments. A “digital twin” that describe the process in the virtual domain will allow current approach in AM development to move away from the current trial-and-error methods to a more knowledge-based approach. This knowledge-based approach allows the integration of machine learning and data analytics into AM, fully realising the potential of Industry 4.0.