Stainless steel for a disc brake rotor

Abstract

A martensitic stainless steel for a disc brake rotor includes, in mass percent, C: 0.04-0.10%, Si: at most 1.0%, Mn: 0.1-2.0%, P: at most 0.04%, S: at most 0.01%, Cr: greater than 11.5 to 13.5%, Al: at most 0.1%, N: at most 0.04%, Cu: 0-1.0%, Ni: 0-1.0%, Ti: 0-0.03% and one or more of Nb: 0.01-0.08% and V: 0.05-0.5%, with the value of GP expressed by the following formula being at least 50 (%): GP ⁢ ⁢ ( % ) = 700 ⁢ C ⁢ ⁢ ( % ) + 800 ⁢ N ⁢ ⁢ ( % ) + 20 ⁢ Ni ⁢ ⁢ ( % ) + 10 ⁡ [ Cu ⁢ ⁢ ( % ) + Mn ⁢ ⁢ ( % ) ] - 6.2 ⁢ Cr ⁢ ⁢ ( % ) - 9.2 ⁢ ⁢ Si ⁢ ⁢ ( % ) - 9.3 ⁢ Mo ⁢ ⁢ ( % ) - 14 ⁢ V ⁢ ⁢ ( % ) - 74.4 ⁢ Ti ⁢ ⁢ ( % ) - 37.2 ⁢ Al ⁢ ⁢ ( % ) + 63.2 .

Dependencies are inferred from the claim text.