1100MPa级高性能工程机械用钢的开发.pdfVIP

1 1100MPa 级高性能工程机械用钢的开发 郭 佳 潘 辉 李 飞 （首钢技术研究院，北京 100043 ） 摘 要 设计了 Cr-Mo 和 Cr-Mo-Ni 两种超高强度钢成分，采用 50kg 真空冶炼炉和 550 小轧机进行冶炼和轧制， 随后进行不同温度的回火实验。力学性能测试结果表明，Cr-Mo 成分的热轧板强度达到目标强度，Cr-Mo-Ni 成分 的热轧板强度不够；热处理后，两种成分的实验钢强度均有所提高，但随回火温度的升高有下降趋势；热处理后， 两种实验钢的冲击性能有明显提高。显微组织观察结果表明，热处理温度升高使贝氏体板条特征弱化是强度下降的 主要原因。 关键词 超高强度 热处理温度 贝氏体 Development of 1100MPa Glass Ultra High Performance Steel Guo Jia Pan Hui Li Fei (Shougang Institute of Technology，Beijing ，100043) Abstract Two chemical components were designed for the ultra high performance steels: Cr-Mo and Cr-Mo-Ni types. The steels were smelted by 50kg vacuum furnace and rolled by 550 rolling machine. The plates were heated to the different temperature for 120 minutes. Then the mechanical properties of the steels were measured. The results indicate that strength of Cr-Mo type steels reach the target value and that of Cr-Mo-Ni type steels is lower than the target value. Strength and impact property of the two steels were improved after heat treatment, whereas they are descend with increasing the heat temperature. The microstructure of the steels after heat treatment was observed and the results reveal that boundary of bainite lath become more illegible with the higher heating temperature, which induces the falling of the strength value. Key words ultra-strength, heat treatment temperature, bainite 1 引言 进入 2009 年以来，工程机械行业成为了国家 4 万亿投资直接受益的行业，铁路、公路、水电等基础设 施建设对工程机械需求极大，主要包括铲土运输机械、起重机械、泵送机械、桩工机械、路面机械几大类， 其中高强度钢板主要应用于起重机械和泵送机械。目前，960MPa 以上级别的高强刚主要依靠进口，国内只 有宝钢一家能达到 960MPa 强度级别钢的生产和供货条件。 国际上超高强度钢的生产主要采用淬火+ 回火工艺[1]，还有近年来新发展的在线热处理工艺，如日本 JFE 公司生产的 HYD960LE 和 HYD1100L[2