The electromagnetic stirring process is a well-established production route for semi-solid slurry preparation

however

the skin effects restrained its application scope. In order to overcome the problem

annulus electromagnetic stirring process（AEMS） was presented. The annulus gap could avoid the part of low magnetic induction intensity

so uniform rotating magnetic filed could be generated in the annulus gap compared to conventional electromagnetic stirring

and then uniform temperature field and uniform fine grain in the structure could be obtained. Microstructure of annulus electromagnetic stirring continuous casting billets exhibits rosette structure

which is uniformly distributed into the billets. Compared with conventional electromagnetic stirring

annulus electromagnetic stirring can greatly decrease macro-segregation and micro-segregation.