Titanium is a very active metal element with silvery white. Especially at high temperature, it is very easy to absorb nitrogen, hydrogen, oxygen, so that the plastic and toughness of the weld is reduced, Titanium Pipe and the strength is greatly increased to cause embrittlement. The density of titanium is 4.5g/cm3, Titanium Pipe the melting point is 1668 ℃, in 20 ℃ its coefficient 8.4x10-6/℃, thermal conductivity 16w/(m·k), titanium and titanium alloys have good corrosion resistance, in oxidizing, neutral and chloride ion medium, Titanium Pipe its corrosion resistance is better than stainless steel.

 

Titanium has a strong chemical vivacity at high temperatures. Titanium in 300 ℃ above the rapid absorption of hydrogen, 600 ℃ above fast oxygen absorption, 700 ℃ above fast nitrogen absorption. Therefore, if the titanium in the welding process and after welding cooling process is not effective protection, Titanium Pipe will inevitably cause plastic decline, brittleness increase. The quality fraction of carbon in general titanium is controlled under 0.1%. When carbon exceeds its solubility, it produces a hard and brittle tic, which is meshed and easily causes cracks.

 

Because of the low impurity content of titanium and titanium alloys, it is not easy to produce thermal cracks, but if the welding wire quality is unqualified, Titanium Pipe especially the welding wire has cracks, interlayer and other defects, there is a large number of impurities, it may cause welding hot crack.

 

Porosity is the most common defect in welding titanium and titanium alloys. There are generally two types of pores and fusion lines in the middle of the weld. Titanium Pipe In the welding line the energy of the larger hole is generally located near the fusion line. The formation reason of the weld hole is mainly due to the welding area, especially because of the water and grease pollution.

 

The selection of the welding wire should make the tensile strength of the weld after welding under the normal welding process not less than the standard tensile strength lower value of the annealing state of the base material, Titanium Pipe the plastic and corrosion resistance of the weld after welding is not less than that of the parent material in the annealing state or the same as that of the parent material.

 

Argon purity of welding should not be less than 99.99%, dew point should not be higher than 40 ℃, when bottled argon pressure is less than 0.981MPa is not suitable for use. Argon is used in the area where the surface temperature of weld pool and welded joint is higher than 400 ℃.

 

The groove and both sides of the 25mm inside and outside the surface for cleaning, cleaning procedures are as follows: polishing machine grinding-sandpaper wheel Polish-acetone cleaning. The welding wire is also stained with acetone sponge wipe clean, and carefully inspect the mother material near the groove and the wire has no cracks and interlayer, if there is, after the removal of welding operations. Titanium Pipe After cleaning can not directly carry out the welding operation, to the end of the groove to dry after the operation. If not timely welding, Titanium Pipe the use of self-adhesive tape and plastic sheeting to protect the groove. The cleaning time to the welding time is not more than 2 hours, the welder gloves should be clean, before the use of anhydrous ethanol (or acetone) cleaning, to avoid the cotton fiber attached to the surface of the welding piece.

 

Titanium rod light weight, high strength, superior mechanical properties, excellent corrosion resistance. It is widely used in: aerospace, ships, auto parts, bicycle parts, marine engineering desalination, mariculture, offshore oil drilling, sea water pipelines; power industry in the ocean thermal power station, condenser, steam Turbine Titanium Blade; Chlor-Alkali, Soda Ash, Urea, and Vacuum Salt Chemical Petrochemical Industry Petrochemical; Electrolytic, Electroplating in Metallurgical Industry; Textile, Papermaking, Fuel in Light Industry;