‍Marine titanium welding process

In recent years, many new ships began extensive use of titanium alloy . With the increase in the amount of titanium alloy materials , shipyard welding to Titanium Welded Tubes enhance efficiency , product quality and stability , the need to develop some efficient titanium welding process. TA5 two kinds of titanium Shanghai Jiangnan Shipbuilding in thickness of 4mm Ti70 and 16 mm for welding object, plasma arc welding , laser welding and laser - arc hybrid welding titanium welding three high energy density of the process carried out explore, get the excellent performance of welded joints
A plasma arc welding
Plasma arc welding is the use of plasma arc welding method as a heat source . Gas heated by the arc generated from the solution , a nozzle at high speed compressed by water , and increasing the energy density of the solution from forming a plasma arc. Its stability , heat and temperature are higher than the arc , and thus has a greater penetration power and welding speed . For marine titanium welding tests show that plasma arc with concentrated energy , penetration , side welding good shape , no tungsten inclusions , less porosity , etc. , it is very suitable for welding of titanium and titanium alloys . More plasma arc welding process parameters , when the method is mainly related to the use of orifice nozzle diameter , titanium bicycle frames welding current, plasma gas flow rate , welding speed , shielding gas flow.
Second, laser welding
Laser welding is a focused laser beam as the heat energy generated by the bombardment of the weldment for welding a high -precision welding method . Laser welding due to the high energy density, obtained greater penetration and high welding speed , and because the diameter of the laser beam is extremely small, so narrow weld and heat -affected zone , the welding residual stress and deformation is small . The main parameters of laser welding laser welding power , welding speed , defocusing amount , side-blown gas flow and shielding gas flow. Since the laser welding high welding speed , the welding process generally can not adjust the parameters of the process , so before the formal optimum welding parameters to be determined by a combination of pre- experiments.
Third, the laser - arc hybrid welding
Compared with conventional arc welding and laser welding, laser - arc hybrid welding weld penetration with a large , high process stability , high welding efficiency , strong weld gap bridging ability and welding deformation , etc., can greatly improve the welding efficiency and weld quality. Laser - arc hybrid welding can reduce the workpiece machining accuracy requirements groove welds may be titanium bicycle part improved over time high laser welding shortage and liquid bath due to higher absorption of the laser beam , laser welding can be compared greater penetration and a higher welding speed . Using laser - arc hybrid welding , laser and arc due to the presence of two heat sources , and each heat are more parameters to be adjusted , so make the laser and arc harmonic match with a lot of tests need to be explored .
Jiangnan Shipbuilding technology test results conducted show that plasma arc welding , laser welding and laser - arc hybrid welding excellent joint performance of the welded test plate . Process repeatability, low level requirements for welders , it is very suitable for the production of large quantities of rules seam welding. Mechanical test results showed that: the mechanical properties of butt joints meet the standard requirements, joint strength and ductility in the match with a reliable base metal Ti70; plasma arc welding and laser - arc hybrid welding using low intensity TA10 wire welding Ti70 plates, welding joint seam strength far exceeds the requirements of matches with Ti70 , which makes titanium alloy welding consumables when marine greatly broaden the range of options available in between strength and ductility, toughness seek to better balance.