The traditional mold flux is mainly composed of CaO and  SiO

2

as the base material

supplemented by an appropriate amount of fluxing agent such as CaF

2

and the fluorine-free mold flux is to choose B

2

O

3

、TiO

2

and other suitable flux to replace CaF

2

to achieve the role of green metallurgy.In this paper

the influence laws of heat transfer of the traditional fluorine mold flux CaO-SiO

2

-CaF

2

and new fluorine-free mold flux CaO-SiO

2

-B

2

O

3

and CaO-SiO

2

-TiO

2

flux films are re- viewed from three aspects of basicity

chemical composition and crys

tallization properties of the mold flux. Summarizes the metallurgical workers in nearly a decade of fluoride and fluorine-free mold fluxs film heat transfer of research results

it is concluded that the fluorine-free mold flux silicon calcium borate and perovskite crystal mineral phases and traditional mold flux  cuspidine  have  similar  crystallization behavior

the  content  of B

2

O

3

and  TiO

2

range  from  4%  to8%  and  3%  to 11%  can  effectively  control the heat transfer

thereby reducing the  occurrence  of slab longitudinal  cracks.