10Cr9Mo1VNbN钢无应力时效的组织与性能研究

Study on No-stress Ageing Microstructure and Properties of 10Cr9Mo1VNbN Steel

采用透射电镜、扫描电镜等方法 ,研究了 10Cr9Mo1VNbN钢正火高温回火后 ,在 5 80℃～ 6 6 0℃经 0～ 5 0 0 0h时效的组织和性能的关系。结果表明 :该钢在时效初期阶段 (2 0 0 0h以内 ) ,力学性能有呈规律性的波动 ,尤其是在 5 0 0～ 10 0 0h,强度和冲击韧度值出现最低值 ,硬度出现最大值等现象 ,证明与粗大的碳化物沿原奥氏体晶界呈连续网状析出及碳化物聚集成树枝和鱼骨状分布有关。时效时间超过 30 0 0h以后 ,碳化物的大小、形态和分布基本保持不变 。

Using TEM,SEM and mechanics properties testing instruments, the relations between microstructure and properties of 10Cr9Mo1VNbN steel normalized and tempered at high temperature have been investigated under no-stress ageing at 580℃～660℃ for 0～5000h. The results show that this steel room temperature mechanics properties have a regular change with ageing time, especially at 500～1000h, strength and impact toughness values are lowest and hardness are highest, which are relation to coarse carbide continuous separating along boundary as net and carbide gathering to branches of tree or fishbone. After ageing time exceeds 3000h the carbide size or shape and distribution hold the line and the mechanics properties also do not change with ageing time.