38MnVS6非调质钢中硫化物碲改质工业实践

Industrial practice of tellurium modified sulfides in the non-quenched and tempered 38MnVS6 steels

分析了未改质和改质后的38MnVS6钢中硫化物形态及评级,研究了碲对钢中硫化物二维及三维形貌的影响;通过对成品棒材力学性能的检测分析,研究了碲对38MnVS6非调质钢力学性能的影响。结果表明:碲改质过后钢中硫化物评级从细系3.0级,粗系2.0级下降为细系2.0级,粗系1.5级,法标评级由F级改质为C级;碲改质后钢中90%左右的硫化物长宽比控制在6以内,50%以上控制在1~3,未改质钢中硫化物大多数为长条状,改质过后以断续状和椭球状为主;改质过后38MnVS6非调质钢的屈服强度、抗拉强度、断后伸长率、断面收缩率等力学性能指标均符合技术要求。

The morphology and rating of sulfide in the unmodified and modified 38MnVS6 steels were analyzed by means of metallographic microscope,scanning electron microscope and electrolytic etching.The effect of tellurium on the two-dimensional and three-dimensional morphology of sulfides in the steels was studied.The effect of tellurium on the mechanical properties of the non-quenched and tempered 38MnVS6 steels was studied by testing and analyzing the mechanical properties of the finished bars.The results show that after tellurium modification,the sulfide rating in the steel decreases from fine system 3.0 and coarse system 2.0 to fine system 2.0 and coarse system 1.5.The standard rating is changed from F to C.The aspect ratio of about 90%sulfides in the tellurium modified steels is controlled within 6,and more than 50%is controlled between 1 and 3.Most sulfides in the unmodified steels have the appearance of long strips,which were mainly changed to intermittent and ellipsoid after modification.After modification,the yield strength,the tensile strength,the fracture elongation,the reduction of area and other mechanical properties of the non-quenched and tempered 38MnVS6 steels meet the technical requirements.