钛合金加强框真空电子束焊接应用研究

钛合金加强框是飞机结构的重要构件,其在框段组合时机械连接与潜弧焊焊接方式均存在不足。真空电子束焊接(EBW)是实现钛合金框段组合的新型制造方式,具有显著优势。采用"积木式方法"展开系列试验研究:首先针对不同热处理制度下的TC4-DT焊接试样进行拉伸试验,通过标的参数对比获取合理的焊后热处理制度;然后通过系列焊接标准试样拉伸试验、断裂韧度试验及裂纹扩展率试验,获取基础性试验数据,并对焊接性能进行判断;最后经过短梁试验、部件试验以及机上应用,完成TC4-DT钛合金加强框EBW工程应用。结果表明:TC4-DT钛合金加强框EBW接头力学性能良好,较机械连接质量收益明显。

Electron Beam Welding Application on Titanium Alloy Bulkhead Frame

The titanium alloy bulkhead frame is one kind of the important components in the aircraft structure. It could be fabricated by using the new method of Electron Beam Welding (EBW) for parts assembly. An introduction is taken on the disadvantages of mechanical joints and Submerged Arc Welding for titanium bulkhead frame parts assembly, the advantage of EBW is distinct compared to the other two methods above. The Building Block Approach was adopted in the research of series tests. Firstly, the heat treat procedure of TC4-DT after welding was based on the welding specimen tension results according to specific parameter comparison. Secondly, the data base was built by doing series of experiments of standard specimen in tension, also for fracture toughness and crack growth rate. Finally, the EBW of TC4-DT titanium alloy bulkhead frame was successfully applied on the specific aircraft after doing short beam experiments and component experiments. Good mechanical properties of the welding joints was verified, and the weight reduction was distinct compared to the mechanical joints.