论文部分内容阅读
九江长江大桥,拟采用15MnVN钢H型的焊接杆件。由于焊缝是分布在翼板的一侧,焊后的构件将产生角变形(图1)。根据施工要求,焊后必须矫形以达到一定的平直度。实践证明,金属经过冷作变形之后,会产生应变时效脆性。低碳钢对应变时效比较敏感,一般认为,经冷作变形之后,晶体中位错密度增加,碳、氮等间隙原子容易扩散并聚集在位错周围,阻碍位错在其后加载过程中进一步运动,从而导致钢材的硬化和脆化。有的文献曾对15MnVN(Cu)钢板
Jiujiang Yangtze River Bridge, proposed 15MnVN steel H-type welding rod. As the weld is distributed on one side of the wing, the post-weld components will have angular deformation (Figure 1). According to the construction requirements, after welding must be orthopedic to achieve a certain flatness. Practice has proved that the metal after cold deformation, it will have a strain of aging brittleness. Low-carbon steel is more sensitive to strain aging, generally believed that after cold deformation, the crystal dislocation density increases, carbon and nitrogen interstitial atoms easily diffuse and gathered around the dislocation, impeding the dislocation in the subsequent loading process further Movement, resulting in hardening and embrittlement of steel. Some literature has on 15MnVN (Cu) steel