15-5PH钢K-TIG焊熔池流动行为分析  

Analysis of flow behavior in K-TIG molten pool of 15-5PH steel

作　　者：冯涛[1] 吕祚翔 刘俊[1] 段琼[1] FENG Tao;LV Zuoxiang;LIU Jun;DUAN Qiong(China University of Petroleum,Qingdao 266580,China;Changling Branch of Sinopec Catalyst Co.,Ltd.,Hunan,Yueyang 414012,China)

机构地区：[1]中国石油大学(华东),青岛266580 [2]中国石化催化剂有限公司长岭分公司,湖南岳阳414012

出　　处：《焊接学报》2021年第8期91-96,I0006,共7页Transactions of The China Welding Institution

摘　　要：采用K-TIG焊实现15-5PH钢中厚板的焊接,并借助示踪法研究K-TIG焊熔池的流动行为.结果表明,KTIG穿孔型焊接时,焊缝上部为马兰戈尼对流圈,下部为表面张力与洛伦兹力导致的对流圈,两个对流圈中间为过渡区.示踪法表明,熔池上部和下部W元素呈弧形分布于对流圈外围,而在过渡区中W元素未出现明显形状.熔池下方对流圈EDS分析结果表明,熔池下方的熔融金属以内旋方式流动.熔池流动计算及试验结果均表明,熔池上部和下部流动剧烈,但是中间层流动加速度很小,且随着焊接热输入的增大,中间层流动加速度有降低的趋势,中间层晶粒有长大趋势.创新点:(1)通过试验和计算,发现在K-TIG穿孔型焊接过程中,熔池分成3个区域.其中熔池中部区域熔融液体流动速度缓慢.(2)通过熔池形状进行表征分析,发现在熔池中部,熔融金属流动的加速度较小,且随着热输入的增加,流动加速度有降低的趋势.K-TIG was used to weld 15-5PH plate.Tracing technique was used to anlysis K-TIG molten pool flow behavior.The welding beam consisted of three parts:the upper part was the marangoni convection circle produced by surface tension,the lower part was the convective circle produced by the interaction of surface tension and lorentz force,and the transition zone between the upper and lower convection circles.The trace method indicated that the W elements in the upper and lower parts of the molten pool were distributed in an arc shape around the convective zone,but the W element was no obvious shape in the transition zone.EDS analysis was carried out on the flow ring under the molten pool,and the results showed that the molten metal under the molten pool flowed by internal rotation.The results of calculation and test show that the upper and lower parts of the molten pool flowed violently,but the flow velocity of the middle layer was small.With the increase of welding heat input,the flow velocity of the middle layer had a tendency to decrease,and the grain size of the intermediate layer tended to grow.Highlights:(1)Through test and calculation,it is found that the weld pool is divided into three areas in the process of k-tig through-hole welding.The flow velocity of molten liquid in the middle of molten pool is slow.(2)Through the characterization analysis of the shape of the molten pool,it is found that the acceleration of molten metal flow is small in the middle of the molten pool,and the flow acceleration tends to decrease with the increase of heat input.

关 键 词：15-5PH钢 K-TIG焊 示踪法 熔池流动加速度 

分 类 号：TG406[金属学及工艺—焊接]