钽换热器管板焊接接头温度场数值模拟

Numerical Simulation on Temperature Field in Tantalum Tube and Ta/16 MnR Clad Sheet Welded Joint

分析了利用钽做换热管、Ta/16MnR复合板做管板的管板式换热器,影响管板焊接接头焊接质量的关键因素。在焊接过程中,高温下形成的金属间化合物(Fe2Ta)是引起焊缝开裂的主要原因。对四种尺寸组合焊接接头的温度场进行了数值模拟数值。结果表明,合理选择钽-钢复合板的钽层厚度可以避免Fe2Ta的形成,为了使钽-钢复合板钢层在焊接过程中不出现熔化,保证焊接接头质量,钽层厚度要达到2.5 mm,这一模拟结果得到了试验验证。

In the case of one heat exchanger consist of tantalum （Ta） tube and Ta/16MnR clad sheet, the key factors for quality of welding joint between heat - exchanging tube and tube - plate was discussed. During welding process , inter-metallic compounds （Fe2Ta） which produced at 1460℃ was the primary factor caused the welding joint cracking. By using ANSYS, the temperature field of tube to tube sheet argonarc welding joint which consist of tantalum （Ta） tube and Ta/16MnR clad sheet was simulated. It deals with four kinds of welding joint. The numerical simulation results show that the thickness of tantalum layer of Ta/16MnR clad sheet was primary factor for welding quality. The tantalum layer of Ta/16MnR clad sheet need 2.5mm, otherwise the 16MnR steel beneath tantalum layer would melt and intermetallic compounds （Fe2Ta） would produced. The numerical simulation result has been substantiated by the experimental results in reference.