Effects of Ti addition on the microstructures and mechanical properties of the Al–Mn–Mg–RE alloy

• Higher addition of Ti (near peritectic point) was added to the Al–Mn–Mg–RE alloy.
• Grains and constituent particles were both refined with the addition of Ti.
• Morphology and distribution of iron-rich phase were meliorated with Ti addition.
• Mechanical properties were improved evidently with Ti addition.

The effects of higher Ti addition (near peritectic point) on microstructures and mechanical properties of a designed Al–Mn–Mg–RE alloy were investigated by optical microscopy, scanning electron microscopy, energy dispersive spectroscopy and tensile tests, respectively. The results show that the addition of Ti refined grains evidently, meliorated the morphology and distribution of iron-rich phase, and hence improved the mechanical properties of the Al–Mn–Mg–RE alloy. The fracture mechanisms changed from brittle fracture to ductile fracture after extruding. The addition of Ti refined the constituent particles and resulted in deeper and more homogenized dimples of the tensile fracture surfaces.