Additive friction stir processing
Tan, Terence Jia Yu
Date of Issue2017
School of Mechanical and Aerospace Engineering
3D printing have increasing becoming popular over the years, Selective Laser Melting (SLM) was used of fabricated composite alloy like AlSi10Mg and AlSi10Mg-Al2O3. By using optimised parameter for AlSi10Mg and Al2O3 that are uniformly and evenly fused and coated together and were fabricated into 3 difference specimens have successfully preformed and tested. The microstructure evolution were observed that the grains before and after FSW have reduces in grain size. From growing along the thermal gradient before FSW to fine equiaxed grains. Besides that, FSW soften the material and eradicated most of the porosity in the zone. Which proof that FSW is able to produce a defect-free joint. Moreover, having alumina in the specimens resulted in an increase in hardness value. Mainly due to grain refinement during FSW. The alumina particles have extra effect on the grain growth. The fracture site could be due to short plastic deformation could be due to welding defect around the area or lack of heat input parameter which resulted to “lazy S” defect. The possibly due to the presence of alumina in the specimens. Additional of alumina into the composite improved the mechanical properties of the material which could be possibly reinforced the material by redirecting the crack around it and having bigger porosity and larger dimples in the specimens can led to a fractured along it grain boundaries.
Final Year Project (FYP)
Nanyang Technological University