Titanium alloy has low density, high specific strength, good corrosion resistance, low thermal conductivity, non-toxic and non-magnetic, and can be welded. It is widely used in aviation, aerospace, chemical industry, petroleum, electric power, medical treatment, construction, sporting goods and other fields.

The commonly used welding methods of titanium and titanium alloy are: argon arc welding, submerged arc welding, vacuum electron beam welding, etc.           

Preparation before welding            

The surface quality of weldment and titanium welding wire has a great influence on the mechanical properties of welded joint, so it must be cleaned strictly.            

  1) mechanical cleaning of weldments with low welding quality requirements or difficult pickling can be wiped with fine sandpaper or stainless steel wire brush, but it is better to scrape titanium plate with hard alloy yellow to remove oxide film.            

  2) chemical cleaning: before welding, the test piece and welding wire can be pickled, and the pickling solution can be HF (5%) HNO3 (35%). Wash with clean water after pickling and weld immediately after drying. Or use acetone, ethanol, carbon tetrachloride, methanol, etc. to wipe the groove of titanium plate and its two sides (within 50 mm each), the surface of welding wire, the part of fixture contacting with titanium plate.            

  3) selection of welding equipment: for TIG welding of titanium and titanium alloy tungsten plate, the DC TIG welding power with external characteristics and high frequency arc striking shall be selected, and the delay time of gas delivery shall not be less than 15 seconds to avoid oxidation and pollution of welding parts.            

  4) selection of welding materials: the purity of argon shall not be less than 99.99%, the dew point shall be below - 40 ℃, and the total mass fraction of impurities shall be 0.001%. When the pressure in the argon cylinder drops to 0.981mpa, the use shall be stopped to prevent affecting the quality of the welding joint. 

  5) gas protection and welding temperature: during the welding of titanium pipe joint, in order to prevent the welding joint from being polluted by harmful gases and elements under high temperature, necessary welding protection and temperature control must be carried out for the welding area and weld joint, and the special protective drag cover shall be used for all-round protection, and the temperature shall be below 250 ℃.        

Operation essentials            

1. During manual argon arc welding, the minimum angle between welding wire and weldment shall be kept (10 ~ 15 °). The welding wire shall be fed into the molten pool smoothly and evenly along the front end of the molten pool, and the end of the welding wire shall not be moved out of the argon protection zone.            

2. During welding, the welding gun does not swing laterally. When it needs to swing, the frequency should be low, and the swing amplitude should not be too large, so as to prevent affecting the protection of argon.            

3. When the arc is broken and the weld is closed, continue to apply argon protection until the weld and the metal in the heat affected zone are cooled below 350 ℃, and then remove the welding gun.        

Weld and HAZ surface color            

1. Weld area            

Silver white, light yellow (grade I, II and III welds are allowed); dark yellow (grade II and III welds are allowed); 

golden purple (grade III welds are allowed); dark blue (grade I, II and III welds are not allowed).            

 2. Heat affected zone            

Silver white, light yellow (grade I, II and III welds are allowed); 

dark yellow, golden purple (grade II and III welds are allowed); dark blue (grade III welds are allowed)

 EST Titanium was established in 2009, so we had more experience in manufacturing, processing and selling high quality and most cost-effective titanium welding wire for many years，Titanium filler wire,MIG Wire,TIG Wire etc,if any inquirys pls do not hesitate contact us!

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