Effects of untreated

Sr and B compound modification

pulsed magnetic field and composite treatment of pulsed magnetic field and modifier on microstructure and mechanical properties of as-cast and T6-state Al-6 Si-3 Cu-0.3 Mg alloy were investigated.Effects of pulse voltage and frequency on microstructure and mechanical properties of the alloy under compound treatment condition were also analyzed.The results show that modification treatment

pulse magnetic field treatment and compound treatment of pulsed magnetic field and modifier can all improve microstructure and mechanical properties of as-cast and T6-state alloy

however the effect of composite treatment presents more remarkable.Compared with those of the untreated alloy

the tensile strength and elongation of as-cast alloy are increased by 59%and 71%

respectively.The tensile strength and elongation of T6-state alloy are increased by 74%and 30%

respectively.In the range of 0～300 V

with the increase of pulse voltage

microstructure of as-cast and T6-state alloy is refined gradually.The tensile strength of as-cast and T6-state alloy and elongation of T6 alloy are increased gradually

while the changes of elongation of as-cast alloy can be ignored.In the range of 1～5 Hz

with the increase of pulse frequency

microstructure of as-cast and T6-state alloy is refined at first and then coarsened

and the turning point is 5 Hz.The change law of tensile strength is the same as that of the microstructure.However

when the pulse frequency is 10 Hz

the elongation of as-cast and T6-state alloy is further improved.