摘要:
采用低碳Cr-Mo系添加微量强碳化物形成元素的成分设计,通过TMCP工艺控制,获得均匀铁素体/贝氏体组织,充分发挥析出强化、细晶强化和贝氏体组织强化作用,研制80 mm厚高韧性工程机械用Q460钢。试制钢板力学性能均匀,不仅具有良好的拉伸力学性能,且低温冲击韧性优良,-60℃冲击功大于180 J,冲击断口呈明显塑性变形;SEM分析表明,断口微观形貌韧窝特征明显,面积约为55%,韧窝内圆形氧化物夹杂细小;钢板厚度方向铁素体/贝氏体组织均匀,晶粒尺寸约为8～10μm;TEM分析表明,晶内存在高密度位错,大量细小弥散的第二相粒子沿位错线析出。
Abstract:
Based on low carbon and Cr-Mo with powerful carbide added,the 80mm thick Q460 grade plate for engineering machinery use was successfully trial-produced by TMCP process.Ultrafine grain and precipitated phase and bainite were fully taken advantage of to increase strength.By means of metallographic examination and inspection of mechanical properties,the results showed that the studied steel was composed of uniform ferrite and bainite,and had good mechanical properties including tensile property and low temperature impact toughness;AKV under-60 ℃ was more than 180 J,and the impact fracture exhibited plastic deformation;SEM analysis showed that the area of dimple fracture was about 55%,and small inclusion in dimple was circular oxide.The result of TEM showed that high density dislocation existed in crystalline grain,and a large number of dispersed fine second-phase particles were separated out along dislocation line in the steel.
点击查看大图
下载:
