Patent ID: 8124008

Claim:
A low carbon free cutting steel containing 0.02 to 0.15 mass % of C, 0.05 to 1.8 mass % of Mn, 0.20 to 0.49 mass % of S, more than 0.01 mass % and not more than 0.03 mass % of O, 0.3 to 2.3 mass % of Cr, not more than 0.1 mass % of Si, 0.01 to 0.12 mass % of P, not more than 0.01 mass % of Al, less than 0.03 mass % of Pb and the balance consisting of Fe and inevitable impurities, wherein a ratio of Cr/S falls within a range of between 2 and 6, said steel containing sulfides such that sulfides having a major axis of at least 10 μm occupy at least 90% of all the sulfides, and sulfides having an aspect ratio not larger than 5 occupy at least 80% of the sulfides having a major axis of at least 10 μm.