摘要
采用自主开发的焊材,对我国研制的G115新型马氏体耐热钢进行了小口径管焊接工艺试验,分析了接头的显微组织,测试了接头的力学性能。结果表明,G115小口径管的焊接工艺性良好,在常规GTAW工艺下焊接可以得到无缺陷的焊接接头,接头的常温拉伸和弯曲性能均满足相关要求。焊缝在焊态下的韧性很低,经过760℃×1.5 h的焊后热处理后,其冲击吸收能量由6 J提高到80 J以上。焊后热处理后,启裂区的断裂机制由解理转变为韧窝,明显提高了裂纹萌生需要的能量。G115焊接接头仍然存在细晶热影响区(FGHAZ)和软化带,软化带出现在靠近母材的临界正火区。
Using self-developed welding material,the welding procedure test was performed for small dimameter tube of new martensitic heat resistant steel G115 developed in China.The microstructure of the G115 welded joint was observed and its mechanical properties were tested.The results show that the welding process of the G115 small dimameter tube is good and the joint without defects can be obtained by conventional GTAW process.The room temperature tensile and bending properties of the joint meet the relevant requirements.The toughness of the weld seam in welded state is very low.After the postweld heat treatment(PWHT)at 760℃for 1.5 h,its impact absorption energy increases from 6 J to more than 80 J.After PWHT,the fracture mode of the crack initiation area changes from cleavage to dimple,which increases the crack propagation energy.There are still fine grain heat-affected zone and softening zone in the joint,softening occurs in the intercritical heat-affected zone near the base metal.
作者
章亚林
王立玉
王学
张鹏
黄桥生
ZHANG Yalin;WANG Liyu;WANG Xue;ZHANG Peng;HUANG Qiaosheng(CHN Energy Science and Technology Research Institute Co.,Ltd.,Wuhan 410066,China;China Energy Engineering Group Jiangsu No.1 Electric Power Construction Co.,Ltd.,Nanjing 210001,China;School of Power and Mechanics,Wuhan University,Wuhan 430072,China)
出处
《热加工工艺》
北大核心
2024年第1期75-78,83,共5页
Hot Working Technology
基金
国家自然科学基金项目(52174370)。
关键词
G115钢
马氏体耐热钢
力学性能
显微组织
G115 steel
martensitic heat resistant steel
mechanical properties
microstructure
