TP347H钢焊接接头微观组织及断口形貌分析

采用了ER316L和H1Cr18Ni9Ti焊丝对TP347H钢的焊接性进行了研究,测试了焊接接头在常温下的力学性能,对焊缝金属和热影响区进行微观组织观察,并对冲击试件进行了SEM断口形貌分析.发现氧化物等杂质容易聚集在热影响区,内充氩不当在焊缝根部极易形成氧化裂纹,焊接参数大容易引起焊缝区未熔合,在启裂处有脆性断裂迹象.通过分析对TP347H钢的焊接性及工艺参数有了更清楚的认识,对大参数火电机组和核电机组材料的焊接具有一定的帮助.

WELDED JOINT MICROSTRUCTURE AND FRACTURE STRUCTURE OF TP347H STEEL

The weldability of TP347H was studied using wires ER316L and H1Cr18Ni9Ti. The mechanical properties of welded joint were tested. The microstructure of weld metal and HAZ (Heat affected zone) were investigated, and the fracture structure of impact test specimens was analyzed by means of scanning electron microscope. The results show that the impurities, such as oxides, gathered easily in HAZ; the oxidation crack was formed easily in HAZ if root in unsuitably inner Ar filling; the lack of fusion in weld metal zone was formed with high-current parameters, so there was brittle rupture characteristic in the fracture zoon. Knowing full well about the weldability and weld process of TP347H through analysis as mentioned above, it will be helpful for the welding of larger fire power and nuclear power set steels.