Four grades of super-purifying ferritic stainless steel 409LI
439M
460LI and 470LI without containing Ni and Mo are pilot-produced by using a new 150 t VD/VOD unit with EAF-AOD-VOD three steps process at AST
ThyssenKrupp. Production practice shows that the refining operation cycle time of EAF-AOD-VOD three steps process is obviously less than that of EAF-VOD two steps process to realize the process goal for production of super-purifying ferritic stainless steel with low cost; and the corrosion resistance and heat resistance of produced new generation super-purifying ferritic stainless steel AST460LI (% : ≤0. 010C
21. 0 ~21. 4Cr
≤0. 002S
0. 10-0. 20Ti) and AST470LI (% : ≤0. 007C
23. 8 ~24. 2Cr
≤0. 002S
0. 10 〜0. 20Ti) are higher than that of standard austenitic stainless steel 304 (% : W0. 08C