Effect of Wire Feeding Speed on Microstructure and Properties of Laser Welding-brazing Joint of Aluminum/Steel
The laser welding-brazing experiment of 6061-T6 aluminum alloy/Q235 galvanized steel dissimilar metal was carried out with ER2319 wire as filler metal,and the effect of wire feeding speed on the joint forming,microstructure and mechanical properties was studyed.The results show that when the laser power is 1.2kW,the welding speed is 1.2 m/min and the wire feeding speed is 1.2-3.0 m/min.,effective joints can be obtained.The tensile strength of the joint increases firstly and then decreases with the increase of the wire feeding speed.When the wire feeding speed is 2.4 m/min,the average tensile strength reaches the maximum value,which is 116.15MPa.When the wire feeding speed is 1.8 and 2.4 m/min,the intermetallic compound layer on the upper and lower surface of the joint can be controlled within 10 μm.However,the thickness of intermetallic compound layer at the butt interface does not change significantly with the change of wire feeding speed.The IMC layer in the joint consists of FeAl,FeAl2 and Fe4Al13 phases.The fracture form of the joint is a typical model of cleavage fracture,while it is ductile fracture at the aluminum alloy position on the steel surface.
NETL
NSTL
万方数据
