低合金奥－贝球铁电弧焊焊条的研究

Development of a low-alloy electrode for arc welding of austempered ductile iron

本文通过等温热处理系统地研究了Ｃｕ、Ｎｉ、Ｍｏ对球铁焊缝金属等温转变，奥－贝化能力及机械性能的影响，井利用Ｘ射线衍射仪、扫描电镜、透射电镜研究了低合金奥－贝球铁焊缝的基体结构，分析讨论了其强韧化机制，在此基础上首次研制成功了Ｎｉ－Ｍｏ低合金奥－贝球铁析焊分，与非合金化奥－贝球铁焊条相比，焊缝金属的奥－贝化能力提高２．５倍，其焊缝与焊接接头的机械性能均满足奥－贝球铁的要求。

Effects of Cu, Ni and Mo on the isothermal transformation,austemperabilityand mechanical properties of ductile iron weld metal were systematically investigated andthe matrix structure of austemoered ductile iron weld was examined with scanning elec-tron microscope and transmission electron microseope.On this basis a Ni-Mo low al-loy electrode for arc welding of austempered ductile iron was developed for the firsttime,The austemperability of the Ni-Mo low,alloy weld metal increases by 2.5 timesas compared with that of the unalloyed weld metal and the mechanical properties ofthe weld and welded joint can match the requirement of austenpered ductile iron.