锻造工艺对2Cr11Mo1VNbN钢横纵向组织及性能的影响

 为了解决2Cr11Mo1VNbN钢横纵向性能差异大的问题，采用OM、SEM等手段研究了不同墩拔工艺下超(超)临界叶片用2Cr11Mo1VNbN马氏体耐热钢的组织、室温力学性能及短时持久性能。结果表明，增加墩拔次数，对合金纵向的强度、塑性及冲击性能影响不明显；对合金的横向性能的影响主要体现在冲击性能和断面收缩率，当二次墩粗和二次拔长以后，横向冲击性能和断面收缩率明显提升。这主要是因为在经过多道次的墩拔工艺后，大颗粒的一次NbC析出破碎，同时在多次加热过程中进一步回溶，使NbC长度方向尺寸明显降低，降低了裂纹形成和扩展速率，性能得到提升。

Effect of forging process on microstructure and property of#br# 2Cr11Mo1VNbN heat resistant steel

 In order to solve the problem of large difference in transverse and longitudinal properties of 2Cr11Mo1VNbN steel， OM and SEM were used to investigate the evolution of microstructure and mechanical properties of 2Cr11Mo1VNbN martensitic heat resistant steel for super (super) critical blades under different forging processes. The results show that the increase number of upsetting and stretching has little effect on the longitudinal properties including strength，plasticity and toughness. The transverse properties including toughness and area reduction improved by double upsetting and stretching processes. The size of primary NbC decreased during deformation and heating treatment processes，which resulting the decrease rate of crack formation and expansion during impacting test.