摘要
精轧PSB830螺纹钢筋材料为40Si2MnVCr钢,淬火、回火后断后伸长率偏低,不合格。为此,对不合格的钢筋进行了力学性能测定、化学成分分析、断口分析、夹杂物检测和金相检验。结果发现,钢筋的回火不充分,这是钢筋断后延伸长率不合格的主要原因。为此对钢筋进行了(450~500)℃×90 min回火处理,结果钢筋的塑性大幅度提高,满足了标准要求。
Finished PSB830 deformed bar,made of 40Si2 MnVCr steel,exhibited elongation that was lower than the desired value after being hardened and tempered.For this reason the unqualified deformed bar was subjected to mechanical property measurements,chemical composition analysis,fracture test,inclusion detection,and metallographic examination.The results indicated that the deformed bar did not be sufficiently tempered,which was a main reason why the elongation was on the low side.In view of the above the deformed bar was tempered at 450 to 500 ℃ for 90 min after hardening with the result that the deformed bar produced much higher elongation,conforming with the requirements.
出处
《热处理》
CAS
2017年第4期40-44,共5页
Heat Treatment
