Abstract: The production flowsheet of developed 0. 020% ~ 0. 060% S steel XGML40Cr (/% : 0. 38 ~ 0. 44C, 0. 17 ~0. 30Si, 0.60 ~0. 80Mn, ≤0. 035P, 0. 020 ~0. 060S, 0. 90 〜1.1OCr, ≤ 0. 01A1) for drill bit at Xingsteel is 50 t BOF-LF-285 mm x320 mm bloom casting-hot-rolling to Φ12 mm wire rod. The cutting test on 0. 027% S steel XGML40Cr and 0. 006% S steel ML40Cr with cutting feed rate 0. 015 mm/r, depth of cut 0. 1 mm and cutting speed 12 〜30 mm/min has been carried out. Test results show that the cutting performance of steel XGML40Cr is better than that of steel ML40Cr, i. e. its turning chip length is 1/5 ~ 3/5 that of steel ML40Cr； the heat productivity of steel XGML40Cr during cutting process is lower than that of steel ML40Cr, its blue turning chip ratio is 10% but that of steel ML40Cr is up to 70% ； and the cutting deformation coefficient of steel XGML40Cr is lower than that of steel ML40Cr and its surface roughness ( Ra 10. 2μm) is better than that of steel ML40Cr (Ra 22. 4μm). The mechanical properties of steel XGML40Cr is about equal to that of steel ML40Cr, its mechanical properties quenched at 870 °C and tempered at 500 ℃ are tensile strength 1 082 MPa, reduction of area 70% , HRC hardness value 40 and impact energy A_kv2 72 J.

摘要： 邢钢开发的0.020%0.060%S钻头用XGMI40Cr钢（/%:0.38~0.44C,0.170~.30Si,0.60~0.80Mn,≤0.035P,0.020~0.060S,0.90~1.10Cr,≤0.01Al）的生产流程为50 t BOF-LF-285 mm×320 mm坯连铸-热轧成Φ12 mm线材。对0.027%S的XGML40Cr和0.006%S的ML40Cr盘条试样进行进刀量0.015 mm/r,切削深度0.1 mm,切削速度1230 m/min的切削试验。试验结果表明,XGML40Cr断屑性能优于ML40Cr,其切削长度为ML40Cr钢1/53/5,XGML40Cr切削过程产生更低的切削热,蓝色切屑比例为10%,ML40Cr钢为70%,XGML40Cr切屑变形系数低于ML40Cr,XGML40Cr表面粗糙度（Ra 10.2μm）优于ML40Cr（Ra 22.4μm）。含硫XGML40Cr钢的力学性能与ML40Cr相当,870℃淬火和500℃回火后的力学性能为抗拉强度1 082 MPa,断面收缩率70%,HRC硬度值40,冲击功A_kv272 J。