无磁钻铤用Cr-Mn-N奥氏体不锈钢组织性能研究  

Research on Microstructure and Properties of Cr-Mn-N Austenitic Stainless Steel for Non-Magnetic Drilling Collar Application

作　　者：邹章雄[1,2] 郎宇平[2] 屈华鹏[2] 项金钟[1] 

机构地区：[1]云南大学物理科学技术学院,云南昆明650091 [2]钢铁研究总院特殊钢研究所不锈钢及耐蚀合金研究室,北京100081

出　　处：《热加工工艺》2013年第18期147-152,共6页Hot Working Technology

基　　金：科技部"十二五"科技支撑计划课题(2012BAE04B01)

摘　　要：研究了热处理工艺以及N元素含量对无磁钻铤用Cr-Mn-N奥氏体不锈钢再结晶过程、析出行为和力学性能的影响，为防止CrzN型析出物的产生加入了少量的稳定化元素Nb。微观形貌观察结果表明：N含量为0．62wt％的热轧态样品经950℃退火处理2～3min后再结晶过程完成，退火时间超过5min会导致等轴晶晶粒长大。基体中观察到大量纳米级弥散分布的点状Nb氮化物。同时还有平均颗粒尺寸1～2μm的Nb．Cr．Fe金属间化合物型析出物，该型析出物经1050℃保温5min后可充分固溶。在600-900℃保温均可造成该型析出物的产生。N含量为0．78wt％的样品室温屈服强度和抗拉强度分别达到880和1100MPa，比N含量为0．62wt％的样品均高100MPa左右，表明N含量从0．62wt％提高至0．78wt％后具有显著的强化作用。Nb-Cr-Fe型析出物所导致的室温韧性显著恶化问题可以通过对其充分固溶处理来解决。The effects of heat treatment and Nitrogen content on recrystallization process, precipitation behavior and mechanical properties of Cr-Mn-N austenitic stainless steel for non-magnetic drilling collar （NMDC） application were studied. Stabilizing element Nb was added in to avoid the formation of Cr2N precipitates. Microstructure observation results show that recrystallization process of specimen with N content of 0.62wt% can be completed after annealing treatment at 950 ℃ for 5 min. Annealing time of longer than 5 min will lead to the growth of equiaxed grains. A great deal of nanometer grade dispersed spot-like Nb nitride is discovered in the substrate. Meanwhile, Nb-Cr-Fe intermetallic compound precipitates with average particle size of 1-2 μm are also observed, which can be thoroughly solution treated after heating to 1050 ℃ for 5 min. The formation of this type of precipitates can occur during heating within temperature range 600-900 ℃. The yield strength and tensile strength of specimen with N content of 0.78wt% are approximately 880 MPa and 1100 MPa, respectively, which are both about 100 MPa higher than that of specimen with N content of 0.62wt%. This results indicate that the N content increment from 0.62wt% to 0.78wt% induces the obvious strengthen effect. The problem of serious room temperature ductility deterioration induced by Nb-Cr-Fe type precipitates can be resolved by fully solution treatment.

关 键 词：无磁钻铤 含N不锈钢 热处理 析出行为 性能 

分 类 号：TG156.2[金属学及工艺—热处理]