Mn18Cr18高氮钢热加工工艺的研究

Research on hot forming process of Mn18Cr18 high nitrogen steel

通过热模拟试验,进行了Mn18Cr18高氮钢的高温热塑性的研究,并对该钢种进行了热锻、热轧试验。结果表明：Mn18Cr18高氮钢的高温热塑性呈“V”字型变化,在1000－1100℃时塑性较差,面缩率仅为20%－30%,在此温度区间进行锻造冲孔时,冲口开裂;在1150－1200℃塑性最好,面缩率可达60%－70%,且变形抵抗较低,是最佳热加工温度区间。按5∶1比例制得的小型护环锻件,力学性能符合JB/T 7030-2002的要求。由于锻件属于多向锻造成形,因此塑性指标优于轧板。

The hot plasticity of Mn18Cr18 high nitrogen steel was studied by thermal simulated test, and the hot forging and hot rolling tests of the steel were carried out subsequently. The results show that the hot plasticity of Mn18Cr18 high nitrogen steel varies with a ＂V＂ shape. It exhibits a dip plasticity value with φ= 20%- 30% when the deformation temperature is between 1000 and 1100 ℃, and the pieces crack during the forging punching tests in this temperature region. In the contrast, the steel exhibits a peak plasticity value with （φ = 60%- 70% between 1150 and 1200 ℃, in addition, low deformation resistance can be obtained in this temperature region. Mechanical properties of the small retaining ring forging scaled down in 5 ： 1 was complied with the standard of JB/T 7030-2002. The ductility of the forgings was much better than the plate for the multiple forging process.