EXTRA-LOW PHOSPHORUS STAINLESS STEEL AND ITS PRODUCING METHOD

摘要

PROBLEM TO BE SOLVED: To provide an extra-low phosphorus stainless steel excellent in corrosion resistance to nitric acid at a low cost and a method with which this extra- low phosphorus stainless steel can further efficiently be produced at a low cost. SOLUTION: In the melting of the stainless steel by using a cold-crucible type float-up melting apparatus, molten flux 5 is interposed between the float-up melted stainless steel 4 and a water-cooling crucible 1, and the phosphorus as impurity in the stainless steel is shifted into the flux by directly inserting the bar-like or the wiry calcium-calcium fluoride base flux 6 into the molten stainless steel to produce the extra-low phoshorus stainless steel.