冷却速率对SEW管坯焊缝性能的影响研究

为了研究不同冷却速率对SEW管坯焊缝性能的影响规律,对两种成分钢管管坯在热张减后不同冷却速率下的管材力学性能和显微组织,及管坯焊缝组织的优化情况进行了试验分析。试验结果表明,对HFW管坯进行热张力减径后经过12~18℃/s速率进行冷却处理,管材延伸率会降低7%,但屈服强度和拉伸强度提升约30%和12%,可实现管材良好的强度和塑性配比。热张力减径后增加管坯冷却速率,可细化焊缝及热影响区晶粒尺寸,有效均匀化焊缝区域和母材的组织。

Research on Influence of Cooling Rate on SEW Pipe Billet Weld Performance

In order to study the influence rule of different cooling rate on SEW pipe billet weld performance, the mechanical properties and microstructure of pipe billet with two kinds of compositions under different cooling rate after hot stretch-reducing were studied respectively, as well as weld microstructure optimization of pipe billet. The study results indicated that after 12~18℃/s cooling process for HFW pipe billet, the elongation was reduced by 7%, but the yield strength and tensile strength of pipe billet was improved about 30% and 12%, it can realize good matching of strength and plasticity. Increasing the cooling rate of pipe billet after hot stretch-reducing can refine grains size of weld and HAZ, and effectively homogenize the microstructure of weld zone and base material.