低成本工程机械用Q690E级高强钢的热处理工艺与工业化

来源期刊：钢铁2011年第6期

论文作者：康健 王昭东 王国栋 刘丽华 梁川

文章页码：86 - 90

关键词：高强钢； 亚温淬火； 调质处理； 显微组织； 性能

Key words：high strength steel； intercritical quenching； quenched-tempered process； microstructure； mechanical property

摘    要：以低成本、高附加值Q690E级调质板开发为目标,研究了亚温热处理与调质热处理工艺参数对试验钢显微组织与力学性能的影响。结果表明:在进行810℃亚温淬火处理的前躯体中存在大块状的铁素体时,易导致试验钢的低温冲击韧性恶化;以板条马氏体为前躯体经相同亚温淬火后,显微结构为更加细小的马氏体和以条状形态呈平行趋势分布在马氏体之间的铁素体两相混合组织,试验钢的-40℃冲击功值高达247 J,但强度较低;常规调质热处理后的试验钢具有良好的综合力学性能,采用修正后的工艺参数,工业试制6~60 mm规格产品的强韧性能均明显超过相关标准要求。

Abstract: In order to develop Q690E high strength steel with low cost and high additional value,the effects of intercritical heat treatment and quenched-tempered process on microstructure and mechanical properties were investigated.The results show that the impact toughness of test steel with prior microstructure containing plenty of massive ferrite can be deteriorated while the intercritical quenching temperature was 810℃.However,by the same intercritical heat treatment,the final microstructure of test steel with prior lath martensite structure consists of much finer martensite and acicular ferrite existed among martensite phase.The Charpy impact energy at -40 ℃ reaches 247 J,but the strength is much lower.The excellent comprehensive mechanical properties can be obtained by quenching and tempering heat treatment.Through the correction of process parameters,the strength and toughness of industrial products(6-60 mm) can meet the standard completely.