回火温度对H10MOD二次硬化钢组织和力学性能的影响  

Effect of Tempering Temperature on Microstructure and Mechanical Properties of H10MOD Secondary Hardening Steel

作　　者：胡春东[1] 曾斌 孟利[1] 董瀚[1] HU Chundong;ZENG Bin;MENG Li;DONG Han(Central Iron and Steel Research Institute,Beijing 100081,China;School of Materials Science and Engineering,University of Science and Technology Beijing,Beijing 100083,China)

机构地区：[1]钢铁研究总院,北京100081 [2]北京科技大学材料科学与工程学院,北京100083

出　　处：《热加工工艺》2018年第20期247-249,253,共4页Hot Working Technology

摘　　要：利用SEM和TEM技术研究了H10MOD二次硬化钢在不同温度下回火的显微组织和力学性能。结果表明：H10MOD钢淬火后在600-700℃回火时,基体中主要碳化物是M2C和M23C6。随回火温度的升高,碳化物的总量逐渐增加,而硬度由47.2 HRC降至26.1 HRC。在600-625℃回火时,冲击韧性保持在34 J左右,几乎没有变化,这说明碳化物对韧性的恶化被位错回复抵消了,此时的断裂机制为准解理断裂;高于625℃回火时,韧性迅速增加,说明位错回复导致的韧性增加量远大于碳化物粗化导致的韧性减小量,此时断裂机制为韧窝断裂。The microstructures and mechanical properties of H10 MOD secondary hardening steel at different tempering temperatures were studied by SEM and TEM. The results show that after quenching and then tempering at 600-700 ℃,the main carbides in matrix of H10 MOD steel are M2 C and M23 C6. With the increase of tempering temperature, the total amount of carbides increases gradually, and the hardness decreases from 47.2 HRC to 26.1 HRC. When tempering at 600-625 ℃, the impact toughness is maintained at about 34 J, almost no change, which shows that the toughness of the carbides is offset by the dislocation recovery, and the fracture mechanism is quasi cleavage fracture; when the tempering temperature is higher than625 ℃, the toughness increases rapidly, which indicates that the increase of toughness caused by dislocation recovery is much larger than the decrease caused by carbide coarsening, and the fracture mechanism is dimple fracture.

关 键 词：二次硬化钢 回火温度 碳化物 H10MOD钢 

分 类 号：TG156.5[金属学及工艺—热处理] TG142.33[金属学及工艺—金属学]