对棒材厂微钒合金英标460钢筋40弯曲断裂试样进行金相观察、断口扫描及能谱分析，发现钢中成分不均、非金属夹杂及连铸坯内裂纹等是造成钢筋弯曲性能不合格的主要原因，并据此提出冶炼、连铸过程中的改进措施，从而使英标钢筋冷弯试验达到100%合格。

The analysis on microstructure, fracture SEM and energy spectrum of bending fracture samples for Britain standard 460 40 mm containing minor vanadium were made. The results showed that heterogenous distribution of compositions, nonmetallic inclusions and internal crack in continuous casting slab are the main origin which lead to disqualification of bending performance. Based on these results, the improving measures in the processes of melting and continuous casting are proposed, and all the cold bending properties are qualified 100%.