Comparative Study on Laser Welding Thick-Walled TC4 Titanium Alloy with Flux-Cored Wire and Cable Wire

Area of Science:

• Materials Science
• Metallurgical Engineering
• Welding Technology

Background:

• Filler material selection critically impacts welding quality in thick-walled titanium alloys.
• Understanding microstructural evolution and mechanical properties is essential for optimizing titanium alloy welding.

Purpose of the Study:

• To compare the welding performance of flux-cored wire versus cable wire in thick-walled titanium alloys.
• To evaluate the macrostructure, microstructure, texture, grain size, and mechanical properties of the resulting welded joints.

Main Methods:

• Welding of thick-walled titanium alloys using flux-cored and cable wires as filler materials.
• Microstructural analysis via optical microscopy (OM), scanning electron microscopy (SEM), and transmission electron microscopy (TEM).
• Evaluation of tensile and impact properties (Charpy impact energy).

Main Results:

• Both joint types featured a basketweave structure of acicular α' martensite in the fusion zone.
• Flux-cored wire resulted in finer microstructures with lower anisotropy.
• Both joints exceeded base metal strength, with flux-cored wire joints showing 16.7% higher Charpy impact energy.

Conclusions:

• Flux-cored wire demonstrates superior performance for welding thick-walled titanium alloys.
• The finer microstructure and enhanced toughness from flux-cored wire contribute to better weld quality.
• This study provides valuable insights for selecting appropriate filler materials in titanium alloy welding.