深冷时间对40CrMnNiMo结构钢组织与力学性能的影响  

Effects of Cryogenic Time on Microstructure and Mechanical Properties of 40CrMnNiMo Structural Steel

作　　者：任媛 REN Yuan(School of Civil Engineering,Chongqing University,Chongqing 400030,China;Department of Civil Engineering,Shanxi Vocational and Technical College,Taiyuan 030006,China)

机构地区：[1]重庆大学土木工程学院,重庆400030 [2]山西职业技术学院建筑工程系,山西太原030006

出　　处：《热加工工艺》2022年第2期142-144,共3页Hot Working Technology

基　　金：国家自然科学基金面上项目(51778086)。

摘　　要：对40CrMnNiMo结构钢进行了900℃×60 min淬火+600℃×120 min回火+不同时间的深冷试验。采用SEM、扭转试验、冲击试验和硬度测试等方法研究了不同深冷时间对40CrMnNiMo钢组织与力学性能的影响。结果表明:与淬火+回火处理的40CrMnNiMo钢相比,淬火+回火+不同时间深冷处理的40CrMnNiMo钢中碳化物更为细小,组织更为均匀致密,其中深冷15 h的40CrMnNiMo钢的组织中碳化物最为细小均匀。随着深冷时间的延长,40CrMnNiMo钢的扭转强度、硬度和冲击吸收能量均先升高后降低,深冷15 h的40CrMnNiMo钢的扭转强度、硬度均达到最大值,分别为982 MPa和38.1 HRC;40CrMnNiMo钢深冷5 h的冲击吸收能量达到最大值72 J。40CrMnNiMo structural steel was subjected to 900 ℃×60 min quenching+600 ℃×120 min tempering+different time cryogenic tests. The effects of different cryogenic time on the microstructure and mechanical properties of 40CrMnNiMo steel were studied by means of SEM, torsion test, impact test and hardness test. The results show that comp ared with the quenching and tempering treated 40CrMnNiMo steel, the quenching and tempering treated 40CrMnNiMo steel with different cryogenic time has finer carbides and more uniform and compact structures, and the microstructure of 40CrMnNiMo steel after cryogenic treatment for 15 h has the smallest and most uniform carbides. With the extension of cryogenic time, the torsional strength, hardness and impact absorbed energy of 40CrMnNiMo steel all first increase and then decrease, and the torsional strength and hardness of 40CrMnNiMo steel reach the maximum value of 982 MPa and 38.1 HRC respectively, after cryogenic treatment for 15 h, the maximum impact absorption energy of 40CrMnNiMo steel after cryogenic treatment for 5 h reaches 72 J.

关 键 词：40CrMnNiMo钢 深冷时间 显微组织 力学性能 

分 类 号：TG156.91[金属学及工艺—热处理]