An Integrated Approach for Alloy Design in Additive Manufacturing: Applications in the Marine Sector

Mohsen Mohammadi, Assistant Professor and Director, Marine Additive Manufacturing Centre of Excellence, University of New Brunswick

Hopeman 224

Additive manufacturing is defined as the process of joining materials layer by layer as small as 20 microns to make objects from 3D CAD models. Of particular interest is Powder Bed Fusion (PBF) techniques that, compared to casting, has fewer restrictions in shape, does not require a mold, offers higher geometrical flexibility, and leads to more complicated parts with reasonable cost meeting the requirements of marine, defence, aerospace, and automotive industries. Specifically, marine parts are often used in harsh environments where corrosion, high fluid flow, shock loads, and hot and cold temperatures are present. Thus, several experiments in different scales should be carried out to assess the microstructure along with physical, electrochemical, and mechanical behaviour of additively manufactured parts under different loading conditions to confirm that they can outperform those produced by conventional methods. To do so, different characterization techniques such as quasi static and dynamic tests along with microscopic analysis (SEM, EBSD, TEM, APT), and X-ray based diffraction methods are used to identify the mechanical and microstructural properties of 3D-printed parts under different loading conditions, i.e. static and dynamic, impact, high and low temperatures, and cyclic loadings. Of particular interest is the microstructural evolution and mechanical properties of different metals mainly used in the marine industry, including stainless steels, aluminum, and bronze alloys.

Marine Additive Manufacturing Centre of Excellence (MAMCE) is a capacity building project established to accelerate the adoption of metal additive manufacturing in Canadian marine sector through research, workforce training, and commercialization. MAMCE aligns with National Shipbuilding Strategy (NSS) and Lloyd’s Register’s “Global Marine Technology Trend 2030”, which includes adopting new technologies such as additive manufacturing, advanced materials, Cyber Security, Augmented Reality, and Industrie 4.0 in the marine sector to stay competitive in the 21^st century.

Dr. Mohsen Mohammadi is currently an Assistant Professor of Mechanical Engineering and Director of Marine Additive Manufacturing Centre of Excellence at the University of New Brunswick. He received his PhD from University of Western Ontario in London, Ontario. He then joined CanmetMATERIALS and University of Waterloo as Visiting Scientist and Postdoctoral Fellow, respectively. The main areas of research of Dr. Mohammadi are “Metal Additive Manufacturing”, “Marine Additive Repair”, and “Shipbuilding Factory of the Future”. Dr. Mohammadi is currently leading significant projects on metal 3D printing in marine, shipbuilding, and defence sectors. Among them is the 12-million dollar industrial initiative to adopt additive manufacturing in the next generations of Canada’s Warships in collaboration with Irving Shipbuilding Inc., J.D. Irving Ltd., Lockheed Martin, and CFM.