Welding Of Gr23 Titanium Alloy

Gr23 titanium alloy welded composite structure not only has titanium alloy high specific strength and good corrosion resistance, but also compatible with the advantages of steel materials with a wide range of applications and cheap price. However, due to the titanium alloy and steel thermal conductivity and coefficient of linear expansion of the difference is too large, and the mutual solubility is poor, welding is easy to generate brittle hard Ti-Fe intermetallic compounds, resulting in titanium alloys / steel dissimilarity welding difficulties.
Dissimilar metal welding refers to the two different types and properties of metal materials through a specific welding process to join together and form a structural component with integrity and expected performance. The thermal conductivity and coefficient of linear expansion of titanium alloys and dissimilar metals are quite different, and brittle intermetallic compounds are likely to be formed during the welding process, leading to deterioration of the strength of the welded joints. Therefore, the addition of appropriate intermediate transition metals in the welding process, the selection of appropriate welding process and welding method is necessary to improve the microstructure and mechanical properties of welded joints.

The chemical composition of grade 23 Ti 6Al 4V ELI alloy is outlined in the following table.

Physical Properties

The physical properties of grade 23 Ti 6Al 4V ELI alloy are tabulated below.