高速列车6N01铝合金型材焊接接头疲劳性能

Fatigue property of 6N01 aluminum alloy welded joint for high-speed train

针对高速列车6N01铝合金型材侧墙部件,采用脉动拉伸试验方法分别测试了母材、单丝MIG焊对接接头、激光-单丝MIG复合焊对接接头、激光-双丝MIG复合焊对接接头的疲劳性能,试验采用升降法进行,应力比为0.1,疲劳寿命设定为1×10~7。疲劳测试结果表明,在该试验条件下,6N01铝合金母材的疲劳强度为115 MPa,与铝合金母材相比,焊接接头的疲劳性能略有降低,单丝MIG焊接头的疲劳强度约为87 MPa,为母材的75.7%,激光-单丝MIG复合焊接头的疲劳强度约为107.5 MPa,为母材的93.5%,激光-双丝MIG复合焊接头的疲劳强度约为105MPa,为母材的91.3%,激光-单丝/双丝MIG复合焊对接接头的疲劳性能优于单丝MIG焊对接接头的疲劳性能。

In order to investigate the fatigue property of 6N01 Al alloy used in high speed train side wall component,the fatigue strength of base material and butt joints welded by single wire MIG,laser-single wire MIG,laser-double wire MIG welding process respectively was measured by pulsed tensile test.The test used the lift method with a stress ratio of 0.1 and a fatigue life of 1 × 10~7.The results show that the fatigue strength of 6N01 aluminum alloy base material is 115 MPa and that of welded joints is slightly lower under this test conditions.The fatigue strength of butt welded joints is about 87 MPa with 75.7% of the base material by single wire MIG welding process,about 107.5 MPa with 93.5% of the base material by laser-single wire MIG hybrid welding process and about 105 MPa with 91.3% of the base material by laser-double wire MIG hybrid welding process.The laser-single/double wire MIG hybrid welding is better than single wire MIG welding with respect to the fatigue strength of butt joint.