直缝焊管用钢焊缝开裂原因分析
|
摘要
采用宏观形貌分析、金属流线观察、断口分析、金相及能谱等手段,分析了某钢厂生产的Q235B带钢裁剪焊管后出现焊缝开裂的问题。认为基体在连铸时内弧厚度方向1/4处存在的偏析和夹杂物,经加热焊接挤压后,破坏了焊缝表面的连续性,在应力作用下形成微裂纹,是造成焊管开裂的主要原因。通过优化冶炼工艺,降低锰硫比等措施使缺陷基本得到控制。
Aiming at the weld seam cracking after tailoring welded pipe of Q235 B strip steel in a steel plant, the causes were analyzed by means of macro-morphology analysis, metal streamline observation, fracture analysis, metallographic and energy spectrum. It is considered that the segregation and inclusions at the 1/4 thickness direction of inner arc of matrix during continuous casting destroy the continuity of weld seam surface after heating, welding and extrusion; and the micro-cracks is formed with stress, which is the main reason for the cracking of welded pipe. Now the defect is basically controlled by optimizing smelting process and reducing the manganese-sulfide.
Aiming at the weld seam cracking after tailoring welded pipe of Q235 B strip steel in a steel plant, the causes were analyzed by means of macro-morphology analysis, metal streamline observation, fracture analysis, metallographic and energy spectrum. It is considered that the segregation and inclusions at the 1/4 thickness direction of inner arc of matrix during continuous casting destroy the continuity of weld seam surface after heating, welding and extrusion; and the micro-cracks is formed with stress, which is the main reason for the cracking of welded pipe. Now the defect is basically controlled by optimizing smelting process and reducing the manganese-sulfide.
引文
[1]中华人民共和国国家质量监督检验检疫总局,中国国家标准化管理委员会.GB/T6394—2017金属平均晶粒度测定法[S].北京:中国标准出版社,2017.
[2]庚英桂.普碳钢直缝焊管焊缝金相组织分析[J]. 轧钢, 1998,(2):24～26.
[3]邓有林,邵丽慧.20钢管焊缝开裂分析[J]. 理化检验(物理分册), 2004, 40(11):578～580.
[4]杨俊, 汤伟, 陈卫金,等. 超低硫钢中硫化锰夹杂的生成机理研究[J]. 金属材料与冶金工程, 2015,(5):9～15.
[5]孙彦辉, 赵长亮, 蔡开科,等.连铸板坯表层网状裂纹的成因研究[J]. 中国冶金, 2008, 18(4):15～20.
[6]Fang L, Ding X F, Jian-Ping H E, et al. Microstructure instability of fully lamellar TiAl alloy containing high content of Nb after long-term thermal cycling[J]. Transactions of Nonferrous Metals Society of China, 2014, 24(10):3095～3102.
[7]崔跃, 魏妍, 黄维全.中厚钢板探伤不合格的原因及预防[J]. 河北冶金, 2014,(2):48～51.
[8]李明贤.王刚,苏富国,等.Q345B热轧钢带冷弯断裂成因及解决方法[J]. 物理测试,2010,(5):42～46.
[9]杨西鹏, 陈文超, 贾贵兴,等. HC250IF冷轧板冲压分层缺陷分析[J]. 河北冶金, 2017,(4):77～81.
[10]张庆军, 曹胜利, 朱立光,等. Q235B热轧带钢冷弯开裂原因分析与对策[J]. 铸造技术, 2015,(12):2905～2909.
[2]庚英桂.普碳钢直缝焊管焊缝金相组织分析[J]. 轧钢, 1998,(2):24～26.
[3]邓有林,邵丽慧.20钢管焊缝开裂分析[J]. 理化检验(物理分册), 2004, 40(11):578～580.
[4]杨俊, 汤伟, 陈卫金,等. 超低硫钢中硫化锰夹杂的生成机理研究[J]. 金属材料与冶金工程, 2015,(5):9～15.
[5]孙彦辉, 赵长亮, 蔡开科,等.连铸板坯表层网状裂纹的成因研究[J]. 中国冶金, 2008, 18(4):15～20.
[6]Fang L, Ding X F, Jian-Ping H E, et al. Microstructure instability of fully lamellar TiAl alloy containing high content of Nb after long-term thermal cycling[J]. Transactions of Nonferrous Metals Society of China, 2014, 24(10):3095～3102.
[7]崔跃, 魏妍, 黄维全.中厚钢板探伤不合格的原因及预防[J]. 河北冶金, 2014,(2):48～51.
[8]李明贤.王刚,苏富国,等.Q345B热轧钢带冷弯断裂成因及解决方法[J]. 物理测试,2010,(5):42～46.
[9]杨西鹏, 陈文超, 贾贵兴,等. HC250IF冷轧板冲压分层缺陷分析[J]. 河北冶金, 2017,(4):77～81.
[10]张庆军, 曹胜利, 朱立光,等. Q235B热轧带钢冷弯开裂原因分析与对策[J]. 铸造技术, 2015,(12):2905～2909.