How to weld titanium alloy without cracking?
2025,07,26
To successfully weld titanium alloys without cracks, a series of protective measures and correct welding techniques are required:
1. Welding protection: Titanium Alloy is very sensitive to harmful gases in the air, so argon or other inert gases should be used for protection during the welding process. You can use a nozzle to eject argon gas to protect the area under the arc, and add a protective shield to the welding gun to protect the welded seam and keep the welding seam cooled to an Ar atmosphere of at least 200 degrees below.
2. Enhance heat dissipation: Due to the small thermal conductivity of titanium alloy, heat accumulation during the welding process may lead to coarse grains in the weld and heat-affected zone (HAZ). In order to reduce this situation, effective methods can be used, such as adding thermally conductive copper pressure plates on both sides of the weld or passing cooling water over the copper pressure plates to help dissipate heat.
3. Select appropriate welding methods and materials: When welding titanium alloys, welding wires with the same composition as the base metal should be used, and consideration should be given to reducing the strength requirements of the welded joints to meet toughness requirements. The choice of welding method is also important. For example, tungsten arc welding is suitable for larger thickness titanium alloy plates, while plasma arc welding requires the use of a mixture of argon and hydrogen in the shielding gas to avoid the risk of hydrides formed between titanium and hydrogen.
4. Preparation before welding: The welding area should be thoroughly cleaned before welding to remove oxide film, grease, moisture and dust. In addition, the gas pressure of the welding equipment needs to be adjusted to ensure adequate gas supply. The selection of welding materials should also be determined based on the specific welding methods and technical requirements.
In summary, successful titanium alloy welding requires comprehensive consideration of welding protection, heat dissipation measures, appropriate welding materials and methods, and sufficient attention to preparations before welding.
