Based On The Strengthening Of The A1Alloying Mg/Ti Resistance Spot Welding And Laser Molten Brazing Research

Weight reduction in ground vehicles and aircraft is one of the important measures toimprove fuel economy and protect the environment. Magnesium alloys, as the lightestmetallic structural alloys, have been and will be increasingly used in the automotive andaerospace industries due to their low density, high strength-to-weight ratio,environmental friendliness, recyclability and castability. people play more and moreattention with them. Taking lighter magnesium alloys replace titanium alloys andaluminum alloys using in aerospace, could lighten their weight. Titanium alloys andaluminum alloys for structure widely use in aerospace, realizing the connection of themagnesium alloy and titanium alloy, magnesium alloy will broaden the scope ofapplication and reduce the consumption of titanium and aluminum. This will reduceweight and save energy. And how to realize the magnesium alloys and titanium alloysconnection is the key technology to solve the problem. Resistance spot welding has theadvantages of little cost, process stable, high efficiency, laser fusion brazing is the mainmethod of connection different alloy. This article will use resistance spot welding andlaser fusion brazing to research the above mentioned problems.The paper took AZ31B magnessium alloys and TC4magnessium alloys as basemetal; Considering Mg and Ti's physical, metallurgy and welding characteristics,resistance spot welding of AZ31B/TC4, selected Al powder as layer additives; influenceof electrode pressure and welding current to weld joint was investigated. The resultindicated, the proper electrode pressure was2100N; within a certain range, the tensileshears increased as the welding current increased, Addition of Al power could improvethe tensile shears. The reason was that there was intermetallic compound on theinterface of weld joint. Laser fusion welding of AZ31B/TC4, selected different solder ofpure Al wire and AZ91D.The results indicated, keeping laser power invariable, weldingspeed and wire feeding speed had great influence on the quality of the welding joint. Soproper welding speed and wire feeding speed were chose. When choose the solder of Al,its quality of welding joint was better than that of AZ91D, because the amount of Al inAl silk was much higher than that in AZ91D, Al and Mg eutectic reaction emerged, theirreaction temperature was low, the reaction zone was wide, so the eutectic reactioncarried out more abundantly. In the solder reaction zone, Al-Mg-Zn compoundsgenerated and distributed among them, brazing interface generation Ti and Alintermetallic generated on the brazing interface.