【摘要】 研究了锻后控冷工艺对中碳含钒微合金38MnVS非调质钢锻件晶内铁素体形成的影响,对锻后不同控冷工艺条件下微合金非调质钢锻件的显微组织、拉伸性能、冲击韧性和冲击断口进行了试验分析。结果表明,在正常的锻造加热温度(1180~1200℃)和终锻温度(1000~1050℃)条件下,采用锻后快冷并在550℃左右保温缓冷的工艺条件,可抑制先共析铁素体沿原奥氏体晶界的析出,获得较多细小条、块状的晶内铁素体,微合金钢锻件的冲击韧性提高了近4倍,同时仍具有较高的强度,且塑性略有提高。更多还原

【Abstract】 Effect of controlled cooling after forging on formation of intragranular ferrite of a medium carbon 38MnVS steel was investigated by analyzing its microstructure,tensile properties,impact toughness and fracture. The results show that when the forging heating temperature and the final forging temperature are 1180- 1200 ℃ and 1000- 1050 ℃,respectively,followed by fast cooling to 550 ℃ and then cooling in furnace,the proeutectoid ferrite precipitation along prior-austenite grain boundries is restrained,and more fine and blocky intragrnular ferrite is observed in the steel. This increasing of intragranular ferrite is contributed to the 4 times increase of impact toughness,and the increasing strength and with slight raising of plasticity.更多还原