PROCESS FOR PRODUCING THIN STRIP OF FERRITIC NON-CORRODING STEEL AND THE THIN STRIP OBTAINED IN SUCH A MANNER

摘要

Manufacture of less than 10 mm thick strip of ferritic stainless steel ( NOTGREATER 0.012% C, NOTGREATER 1% Mn, NOTGREATER 1% Si, NOTGREATER 0.040% P, NOTGREATER 0.030% S and 16-18% Cr) involves (a) (naturally) cooling twin-roll continuously cast strip without holding in the austenitic transformation region; (b) optionally hot rolling at 900-1150 degrees C with≥5% thickness reduction; (c) coiling at between 600 degrees C and the martensitic transformation temperature (Ms); (d) cooling at NOTGREATER 300 degrees C/hr. to between 200 degrees C and ambient temperature; and (e) bell annealing, preferably at 800-850 degrees C for≥4 hrs. Preferably, step (a) is carried out by cooling the strip immediately after leaving the casting rolls, at≥10 degrees C/sec. down to 600 degrees C. Also claimed is ferritic stainless steel strip made by the above process.