Automatic Welding, 2016, №01



2016 №01 (06)

DOI of Article 10.15407/as2016.01.07

2016 №01 (08)

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Avtomaticheskaya Svarka (Automatic Welding), #1, 2016, pp. 47-52

Electron beam weldability of damage-tolerant titanium alloy TC21

Yuan Hong, Zhang Guo-Dong, Wang Jin-Xue, Yu Huai And Zhu Zhi-Shou

Beijing Institute of Aeronautical Materials 100095, Beijing, China. E-mail: hong.yuan@biam.ac.cn
 
 
Abstract
In China TC21 alloy represents itself α + β titanium alloys with tensile strength of 1100 MPa, high fracture toughness and low fatigue crack growth rate. The study of EBW of thick-section TC21 alloy was carried out and mechanical properties of welded joints were evaluated. Testing of fracture toughness and resistance to fatigue crack reveal that their damage tolerance is comparable to that of base metal. The high cycle fatigue strength of the EB-welded joints is 643 MPa, reaching 98.3 % of that of base metal. The microstructure of weld metal consists of coarse columnar dendritic prior β-grains and finer acicular ?-martensite, which accounts for the difference of crack growth rate and fracture toughness between base metal and metal of welded joints. These results indicate that TC21 titanium alloy has excellent EB weldability. 8 Ref., 1 Table, 9 Figures.
 
Keywords: electron beam welding, damage tolerance, fracture toughness, fatigue crack propagation
 
 
Received:                26.11.15
Published:               15.03.16
 
 
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