15MnNbVR压力容器用钢焊接性实验研究

Experimental Study on Weldability of Pressure Vessel Steel 15MnNbVR

针对武钢新研制的压力容器用钢15MnNbVR的焊接性进行了实验研究,采用热影响区最高硬度试验、斜Y型坡口裂纹试验测试了该钢对冷裂纹的敏感性,进行了焊接线能量对焊接接头力学性能影响、焊后热处理温度对焊接接头力学性能影响、低温系列冲击、断裂韧性等试验。结果表明,15MnNbVR钢具有优良的焊接性,焊接接头热裂倾向和再热裂纹敏感性小,焊前预热温度到125℃以上时,产生冷裂纹的可能性较小,低温系列冲击韧性受焊接线能量影响程度不大,具有与母材相当水平的断裂韧性。该钢是制造高参数压力容器、大型储罐和水电站压力钢管等理想材料。

The weldability of pressure vessel steel 15MnNbVR developed by Wuhan iron and steel Co was investigated.The sensitivity of steel 15MnNbVR to cold crack was carried out by the test of maximum hardness of HAZ and Y-groove crack.The effects of welding heat input and post-heat treatment on the mechanical properties were researched.The experiments of low temperature impact and fracture toughness of welded joint was carried out.The results show that steel 15MnNbVR has excellent weldability.The welded joint has small tendency of thermal crack and sensitivity of reheating crack.The cold crack may not appear when preheat temperature is above 125 ℃.The welding heat input has less effect on low temperature impact toughness,which has equal fracture toughness with base metal.The steel 15MnNbVR is applied in the manufacture of high parameter pressure vessel,large storage tank and pressure pipes for large hydraulic power station.