活性剂对铁素体不锈钢A-TIG接头熔深及组织性能研究

目的 选用430铁素体不锈钢作为研究对象，对比研究添加SiO2、TiO2、Cr2O3和未添加活性剂对A-TIG焊接接头显微组织和力学性能的影响。方法 采用3种活性剂涂覆在430铁素体不锈钢上进行A-TIG试验，分析活性剂对接头熔深、组织、性能、元素含量的影响情况。结果 同一焊接工艺参数下，活性剂的加入均能提高焊缝的熔深和深宽比，减少熔宽;其中，SiO2为活性剂时获得了最佳的焊缝几何形貌。同时，对比常规TIG焊接(未添加活性剂)接头的显微组织及力学性能可知，活性剂的加入并未改变焊接接头的显微组织且无新相的生成;活性剂的添加能够细化接头组织，从而使得接头硬度有所提高。结论 活性剂的加入能够显著增加铁素体不锈钢TIG焊缝熔深，改善接头组织，提高接头硬度。

Study on Penetration Depth and Microstructure Properties of Ferritic Stainless Steel A-TIG Welding Joint

The work aims to choose 430 ferritic stainless steel as the research object, and compare the effects of adding SiO2, TiO2, Cr2O3 and no active flux on the microstructure and mechanical properties of A-TIG welded joints. The A-TIG test was carried out on 430 ferritic stainless steel coated with three kinds of active fluxs, and the influence of active fluxs on the penetration depth, microstructure, properties and element content of the joint was analyzed. Under the same welding process parameters, the addition of active flux can improve the weld penetration and D/W ratio and reduce the weld width; among them, the best weld geometry is obtained when SiO2 is used as active flux. At the same time, by comparing with the microstructure and mechanical properties of conventional TIG welded joints (without active flux) , it can be seen that the addition of active flux does not change the microstructure of the weld and no new phase is formed; and the addition of active flux can refine joint organization, so that the joint hardness has been improved. The addition of active flux can significantly increase the TIG weld penetration of ferritic stainless steel, improve the joint microstructure and hardness.