Abstract:
A near eutectic Al−12.6Si alloy was developed with 0.0wt%, 2.0wt%, 4.0wt%, and 6.0wt% Al−5Ti−1B master alloy. The microstructural morphology, hardness, tensile strength, elongation, and fracture behaviour of the alloys were studied. The unmodified Al−12.6Si alloy has an irregular needle and plate-like eutectic silicon (E
Si) and coarse polygonal primary silicon (P
Si) particles in the matrix-like α-Al phase. The P
Si, E
Si, and α-Al morphology and volume fraction were changed due to the addition of the Al−5Ti−1B master alloy. The hardness, UTS, and elongation improved due to the microstructural modification. Nano-sized
in-situ Al
3Ti particles and
ex-situ TiB
2 particles caused the microstructural modification. The fracture images of the developed alloys exhibit a ductile and brittle mode of fracture at the same time. The Al−5Ti−1B modified alloys have a more ductile mode of fracture and more dimples compared to the unmodified alloy.