Patent ID: 8273292

Claim:
A machine part obtained by cutting a steel for machine and structural use having excellent machinability, said steel comprising an oxide inclusion comprising: CaO: 10 to 55 mass %; SiO 2 : 20 to 70 mass %; Al 2 O 3 : more than 0 and 35 mass % or less; MgO: more than 0 and 20 mass % or less; MnO: more than 0 and 5 mass % or less; and one or more members selected from the group consisting of Li 2 O, Na 2 O, K 2 O, BaO, SrO and TiO 2 : 0.5 to 20 mass % in total, wherein a total mass of an average composition of the oxide inclusion in 100 mass %.