Study On The Application Of TA2 A-TIG Welding Process For Industrial Pure Titanium

Titanium has low density,high tensile strength and yield strength,high elongation and excellent corrosion resistance.It is widely used in aviation,aerospace,industry and other fields.Manual tungsten argon arc welding(TIG)is one of the most common welding methods for titanium and its alloys.However,because of single layer welding pool shallow and low depositing is efficiency.It is a necessary to open the groove,fill the welding wire,and carry out multi-layer multi-pass welding and other technological measures.When welding a thickness of 3mm or more.Thereby,the welding manpower and process control increasing the cost.As a new welding method,A-TIG welding has received increasing attention.Before traditional TIG welding,a thin layer of activator is coated on the surface of the weld,which can significantly improve the penetration.Five kinds of composite activator were allocated according to different proportions in this subject.By surface fusion welding,comparing the weld penetration,weld width size and depth-width ratio,an optimum A-TIG welding activator ratio for TA2 plate was selected.The effects of tungsten electrode parameters,welding current,welding speed,shielding gas and activator dosage on penetration,weld width and depth-width ratio of A-TIG welding of TA2 plate were studied.The welding parameters suitable for A-TIG welding of TA2 plate were obtained.The TIG and A-TIG welding of TA2 plate were compared by using the optimum activator and welding parameters.Microstructure and mechanical properties of welded joints after welding were analyzed and compared,and theoretical analysis was carried out.The following results were obtained after research:In A-TIG welding,the diameter of tungsten pole is 2.4 mm,the end shape is conical,and the top angle of the cone is 90 degrees,the weld is formed well.The weld penetration and width increase with the increase of current and decrease with the increase of welding speed.When the welding current is 140-160A,the welding speed is controlled at 140-155mm/min,the deposit amount is 0.21 mg/mm~2,the depth-width ratio of the weld is the largest,and the shape of the weld is good.When TA2 A-TIG torch protects gas flow 12-15L/min,towing cover gas flow 15-20L/min and back cover argon gas flow 25-30L/min,the front and back surface of weld is bright and the protection effect is better.Compared with traditional TIG welding,TIG welding and A-TIG welding can reduce the number of welding layers,prevent oxidation of the weld surface,improve weld formation,and refine the weld microstructure of the weld zone and heat affected zone.At room temperature,A-TIG welding has better tensile strength,impact toughness and Vickers hardness than conventional TIG welding,and has obvious advantages in welding production.In this paper,the influence of the industrial pure titanium TA2 palte A-TIG welding process is studied.The ratio of the industrial pure titanium TA2 sheet active agent and the selected welding process parameters will improve the welding quality of titanium and titanium alloy,improve the welding efficiency and reduce the welding cost.It has important practical significance and broad application prospects.