摘要
对比研究了钛和铌微合金化Q345C钢的显微组织及力学性能。结果表明：两种试验钢均具有较高的屈服强度、良好的延伸性和低温冲击韧性,钛微合金化钢的延展性和低温冲击韧性更好,强度略低;两种钢的组织均由铁素体和珠光体组成,晶粒度均为9-11级;钛微合金化钢中的夹杂物主要为MnS和少量Ti4C2S2,析出物是尺寸为50-250nm的TiN,强化机制主要为细晶强化;铌微合金化钢中的夹杂物主要为MnS,析出物是尺寸为20-100nm的Nb（C,N）,强化机制主要为细晶强化和沉淀强化。
The microstructure and mechanical properties of Ti-microalloyed and Nb-microalloyed Q345 C steels were studied contrastively.The results show that the two kinds of steels both had high strength,good extensibility and excellent low-temperature impact toughness.Ti-microalloyed Q345 Csteel had better extensibility and low-temperature impact toughness,but it had lower strength.The microstrure of the Ti-microalloyed steel was similar to that of the Nb-microalloyed steel,both of them were composed of ferrite and pearlite and the grain sizes were 9-11 grade.For the Ti-microalloyed steel,the main inclusions were MnS and a few Ti4C2S2,the precipitation was TiN with sizes of 50-250 nm,and its strengthening mechanism was fine grain strengthening.For the Nbmicroalloyed steel,the main inclusion was MnS,the precipitation was Nb（C,N）with sizes of 20-100 nm,and its strengthening mechanism was fine grain strengthening and precipitation strengthening.
出处
《机械工程材料》
CAS
CSCD
北大核心
2015年第7期17-21,126,共6页
Materials For Mechanical Engineering
