铁素体珠光体型非调质钢连续冷却转变的研究

采用DIL805L淬火相变膨胀仪研究了铁素体珠光体型非调质钢的连续冷却相变组织变化规律，分析了冷却速率和合金元素对相变组织、显微硬度和CCT曲线的影响。结果表明，Mo有助于获得针状铁素体组织，进而提高韧性，Mn与微合金元素V有助于提高钢的综合力学性能；冷速增大至0.5 ℃/s时，开始出现针状铁素体；冷速小于1 ℃/s时，获得完全的铁素体+珠光体组织；随着冷速的增大，钢的硬度不断增大。

Study on continuous cooling transformation of ferrite pearlite non quenched and tempered steel

Microstructure evolution of ferrite pearlite non quenched and tempered steel during continuous cooling transformation was studied on DIL805L thermal dilatometer.The influence of cooling rate and alloy elements on microstructure,micro hardness and continuous cooling transformation (CCT) curve were analyzed in detail.The results show that the addition of Mo can improve toughness by obtaining acicular ferrite,Mn and micro alloy element V attribute to improve comprehensive mechanical properties of steel.When the cooling rate increases to 0.5 ℃/s,acicular ferrite begin to generate,the microstructure at room temperature are ferrite and pearlite entirely when the cooling rate less than 1 ℃/s.Meanwhile,the hardness increase with the cooling rate increase.