Ge Guangnan, Hu Jin, Hu Zongqiu, Li Haijun, Huo Yan, Tang Shawei, Liu Yi, Ding Junfeng, Hou Shipu, Gao Yunbao
Department of Materials Science and Engineering, Harbin Institute of Technology, Harbin 150001, China.
State Key Laboratory of Hydro-Power Equipment, Harbin 150040, China.
Materials (Basel). 2024 Sep 25;17(19):4708. doi: 10.3390/ma17194708.
In the present work, the Q345B low-alloy steel with different contents and ER309L stainless steel were melted together to obtain new alloys. The aim was to design the composition of weld metal (Q345B low-alloy steel as the base material and ER309L welding wire as the filler material) and improve the corrosion resistance of the weld metal. During the welding process, the composition of the weld metal was controlled to match the new alloys by changing the welding heat input. A relationship curve between fusion ration and welding heat input was obtained. The research focused on analyzing the effect of mixed-smelting ratio between Q345B and ER309L and welding heat input on the microscopic structure and corrosion performance of the prepared samples. The results show that the melted alloys containing 20% to 30% Q345B consist of a ferrite (δ) phase and austenite (A) phase, the samples containing 45% to 50% Q345B consist of a martensite (M) phase and austenite (A) phase, and the sample containing 40% Q345B consists of a martensite (M) phase, ferrite (δ) phase, and austenite (A) phase. As the mixed-smelting ratio of Q345B/ER309L increased, the corrosion resistance of samples decreased gradually. For the weld metal, the fusion ration between Q345B base material and ER309L welding wire increases with the welding heat input. When the heat input changed from 0.645 kJ/mm to 2.860 kJ/mm, the composition of the weld metal was consistent with the melted alloys containing 20-45% Q345B. The microstructure and corrosion resistance of the weld metal could be designed by the melting means, which has important guiding significance for engineering applications.
在本研究中，将不同含量的Q345B低合金钢与ER309L不锈钢一起熔炼以获得新的合金。目的是设计焊缝金属的成分（以Q345B低合金钢为母材，ER309L焊丝为填充材料）并提高焊缝金属的耐腐蚀性。在焊接过程中，通过改变焊接热输入来控制焊缝金属的成分以使其与新合金相匹配。得到了熔合比与焊接热输入之间的关系曲线。该研究重点分析了Q345B与ER309L的混合熔炼比以及焊接热输入对制备样品的微观结构和腐蚀性能的影响。结果表明，含20%至30%Q345B的熔融合金由铁素体（δ）相和奥氏体（A）相组成，含45%至50%Q345B的样品由马氏体（M）相和奥氏体（A）相组成，含40%Q345B的样品由马氏体（M）相、铁素体（δ）相和奥氏体（A）相组成。随着Q345B/ER309L混合熔炼比的增加，样品的耐腐蚀性逐渐降低。对于焊缝金属，Q345B母材与ER309L焊丝之间的熔合比随焊接热输入的增加而增大。当热输入从0.645kJ/mm变化到2.860kJ/mm时，焊缝金属的成分与含20-45%Q345B的熔融合金一致。通过熔炼方法可以设计焊缝金属的微观结构和耐腐蚀性，这对工程应用具有重要的指导意义。
