Fused CaF₂–TiO₂ fluxes have been designed, prepared, and applied in the flux cored wires to join EH36 shipbuilding steels under high heat input electro-gas welding. Ensuing microstructural evolution in the weld metals subjected to varied CaF₂–TiO₂ flux cored wires has been fully documented. It has been demonstrated that as the content of TiO₂ in the fused fluxes increases, columnar grain size increases, and major constituents in the weld metal change from lath bainite, to granular bainite, and then to acicular ferrite. Such phenomena are elucidated via salient chemical reactions involving oxygen pickup and concurrent titanium transfer.

中文翻译：

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高热输入气电焊下不同 CaF2-TiO2 药芯焊丝焊缝金属的微观结构演变研究

熔融 CaF ₂ -TiO ₂助焊剂已被设计、制备并应用于药芯焊丝，以在高热输入电气焊条件下连接 EH36 造船钢。经受不同 CaF ₂ -TiO ₂药芯焊丝处理的焊缝金属随后的微观结构演变已得到充分记录。研究表明，随着熔剂中TiO _{2含量的增加，柱状晶粒尺寸增大，焊缝金属中的主要成分从板条贝氏体变为粒状贝氏体，再变为针状铁素体。}通过涉及氧气吸收和同时钛转移的显着化学反应阐明了这种现象。