合金元素对高锰奥氏体超低温钢性能的影响

Effect of Alloying Elements on Properties of High Manganese Austenitic Cryogenic Steels

研究了Fe-Mn-Cr-N系超低温钢的强度和韧性。试验结果表明,在固溶处理时采用空冷比一般通常采用的淬火快冷能获得更好的性能。随着试验温度降低、钢的强发增加而韧性降低。含氮量较高的钢对温度的变化较为敏感。锰含量对强度影响不大,但对韧性有很大影响。在35%Mn时,Fe-Mn-Cr系钢中的低温冲击韧性达到峰值。随着含氮量的提高,钢的强度近似线性增加。在固溶处理时淬火快冷情况下,铬对韧性的影响在7%Cr时其韧性达到最大值。由于在固溶处理时采用空冷工艺以及在钢中加入铬降低了锰在奥氏体晶界上的偏聚,减少了晶界断裂,因此,大大地提高了具有稳定的奥氏体组织的高锰钢的低温韧性。

The strength and toughness of Fe-Mn-Cr-N cryogenic steels are studied. Test results show that the properties obtained by air cooling process during solution treatment arc better than by rapid quenching which is used in usual solution treatment.The strength is increased and foughness is decreased with decreasing test femperature. Higher nitrogen content steels are more sensitive to variance of temperature.The manganese content has liffle effect on strength but has great influence on toughness. The Fe-Mn-Cr steels have maximum low temperature toughness at 35%Mn. The strength is almost increased linearly with increasing nitrogen conteut. When ropid quenching is used during solution treatment, chromium has the greatest effect on toughness at 7% Cr content. By using the air cooling in solution treatment and addition of chromium to steel, the manganese segregation at austenile grain boundaries is decreased, therefore the low temperature toughness of high manganese full austenitic steels is increased greafly.