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                 试验与研究                                                              DOI:10.11973/lhjy-wl240141


                           焊接热输入对 1 000 MPa 级马氏体钢焊接

                                           接头组织和性能的影响




                                          王 月 ,董现春 ,赵英建 ,李晓林 ,陈树海                 2
                                                                         1
                                                         1
                                                 1
                                                                 1
                       (1.首钢集团有限公司 技术研究院,北京 100043;2.北京科技大学 材料科学与工程学院,北京 100083)
                      摘  要:采用熔化极气体保护焊的方法对1.8 mm厚1 000 MPa级马氏体钢进行了焊接,系统地研
                  究了焊接热输入对焊接接头硬度分布、组织演变及力学性能的影响规律。结果表明:与母材相比,
                  焊缝及热影响区的硬度均发生了不同程度的软化现象,细晶区软化现象最为显著;随着焊接热输入
                  增加,焊接接头的强度及塑性均降低,韧性提高,焊缝区、临界区及亚临界区的硬度略有降低,粗晶
                  区和细晶区的硬度略有升高,焊缝及热影响区的冲击性能无明显变化,接头断裂位置由细晶区变为
                  亚临界区。
                      关键词: 焊接热输入;热影响区;MS1000马氏体钢;力学性能;显微组织
                      中图分类号:TG442;TG457.1;TB31      文献标志码:A    文章编号:1001-4012(2024)07-0005-08

                    The effect of welding heat input on the microstructure and properties of
                                 welded joints of 1 000 MPa grade martensitic steel

                                 WANG Yue , DONG Xianchun , ZHAO Yingjian , LI Xiaolin , CHEN Shuhai 2
                                                                      1
                                                                               1
                                          1
                                                        1
                              (1. Research Institute of Technology, Shougang Group Co., Ltd., Beijing 100043, China;
                   2. School of Materials Science and Engineering, University of Science and Technology Beijing, Beijing 100083, China)
                      Abstract: The welding of 1.8 mm thick 1 000 MPa grade martensitic steel was carried out using the method of
                  melting electrode gas shielded welding. The influence of welding heat input on the hardness distribution, microstructure
                  evolution, and mechanical properties of welded joints was systematically studied. The results show that compared with
                  the base metal, the hardness of the weld and heat affected zone underwent varying degrees of softening, with the softening
                  phenomenon in the fine-grained zone being the most significant. As the welding heat input increased, the strength and
                  plasticity of the welded joint decreased, while the toughness increased. The hardness of the weld zone, critical zone, and
                  subcritical zone slightly decreased, while the hardness of the coarse-grained and fine-grained zones slightly increased.
                  There was no significant change in the impact performance of the weld and heat affected zone, and the fracture position
                  of the joint changed from fine-grained zone to subcritical zone.
                      Keywords: welding heat input; heat affected zone; MS1000 martensitic steel; mechanical property; microstructure

                  随着节能减排意识的增强,轻量化成为汽车工                          减轻各零部件的质量           [3-4] 。为满足轻量化要求,商用
              业发展的主要趋势,开发高强度钢板是实现轻量化                            车上通常选择1 000 MPa级超高强马氏体钢, 替代了

              的有效手段之一        [1-2] 。商用车轻量化的设计原则为:               传统700 MPa级高强钢。近年来,随着热轧技术的
                                                                不断发展,“以热代冷”概念逐渐深化 ,即用同等强
                                                                                                 [5]
              在确保强度、安全性、可靠性等汽车综合性能指标的
                                                                度和规格的热轧产品替代冷轧产品,以实现环保、节
              前提下,兼顾质量、性能、价格等因素,最大限度地
                                                                能和降本等需求,使热轧超高强马氏体钢在商用车
                                                                领域应用广泛。
                 收稿日期:2024-05-21
                                                                     商用车上焊缝数量众多,焊缝质量的好坏直
                 基金项目:国家自然科学基金项目(52275)
                                                                接影响整车的安全性能,因此研究薄规格热轧超
                 作者简介:王 月(1993—),女,博士,主要从事超高强钢焊接
              技术研究工作,13261910217@163.com                        高强钢的焊接性能至关重要                [6-10] 。马彦龙等  [11]  研
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