论文部分内容阅读
采用搅拌摩擦焊方法对高速客车车体用材料7020铝合金板进行焊接,观察了焊接接头的金相组织,测试了焊接接头的拉伸性能、冲击性能及硬度分布。结果表明,采用搅拌头旋转速度1200r/min、焊接速度150mm/min时,抗拉强度高达309 MPa,是母材的78%;焊接接头软化状况比MIG焊接的接头软化程度弱。焊接接头各区组织的不均匀性造成了接头硬度分布不均匀和冲击韧性差异,焊核区为等轴晶粒是其为各区韧性最高的重要原因。
The friction stir welding method was used to weld high-speed passenger car body material 7020 aluminum alloy plate. The microstructure of the welded joint was observed. The tensile properties, impact properties and hardness distribution of the welded joint were tested. The results show that the tensile strength is as high as 309 MPa at the rotating speed of 1200r / min and the welding speed of 150mm / min, which is 78% of the base metal. The softening condition of welded joint is weaker than that of MIG welded joint. Unevenness in the welded joints caused by the organization of the uneven distribution of hardness and impact toughness difference, the weld zone is equiaxed grains is the most important reason for the toughness of the district.