高体积分数SiC_p/2024Al基复合材料添加Ti-6Al-4V中间层激光焊接特性

Study on Welding Process and Microstructure of Laser Welding High Volume Fraction SiC_p/2024Al Matrix Composite with Ti-6Al-4V Filler

高体积分数SiCp/2024Al基复合材料由于大量增强相颗粒的存在,在熔化焊接过程中Al基体极易与SiC颗粒反应,生成Al4C3金属间化合物,严重降低焊缝的力学性能。以Ti-6Al-4V金属薄片作为中间层填充材料,采用氩气作为保护气体,对SiC体积分数为45%的SiCp/Al基复合材料进行激光焊接,分析SiCp/Al基复合材料的焊接特性。结果表明,填充钛合金材料进行CO2激光焊接时接头组织致密,结合较好,在焊缝组织中获得了以Ti3Al为基体、Ti5Si3和TiC等反应产物为增强相的焊缝组织,所获得的最高抗拉强度为母材的50%左右。

The fusion weldability of high volume fraction（45% of SiC） SiCp/2024Al matrix composite is considerably difficult due to the loss of SiC and formation of Al4C3.The Al4C3 will seriously reduce the mechanical properties of the weld.The weldability of SiCp/2024Al matrix composite with 45% volume fraction of SiC is investigated by using a thin Ti-6Al-4V foil as the intermediate material.The results clearly show that the Ti content prevents the formation of Al4C3 during laser welding.The weld appearance is excellent.A weld joint reinforced with Ti5Si3 and TiC is produced.The maximum tensile strength is 258 MPa,which is 50% of the base metal.