(57) A ferritic free-cutting stainless steel excellent in surface roughness and outgass
resistance is disclosed which comprises in weight percentage, 0.06% or less of C,
0.05 to 1.0% of Si, 2.0% or less of Mn, 0.050% or less of P, 0.05 to 0.50% of S, 2.0%
or less of Cu, 2.0% or less of Ni, 9.0 to 25.0% of Cr, 4.0% or less of Mo, 0.065 to
2.0% of Ti, 0.0150% or less of O, 0.020% or less of N, 0.001 to 0.100% of Al, and
Fe and inevitable impurity in the rest portion, wherein the steel satisfies Equations
(1) and (2) of the equations,
where the amount of Ti contained in the steel is represented by [Ti], that of S is
represented by [S] and that of Mn is represented by [Mn], and wherein the steel satisfies
Equation (3) where the amount of Ti contained in sulfide produced in the texture of
the steel is represented by WTi, that of Cr is represented by WCr and that of Mn is
represented by WMn.
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