Microalloying Element Titanium
Titanium is a strong deoxidizer and forms carbide and nitride, which increases strength and controls the austenite grain size.
Physical-Chemical Mechanism of Action
Titanium reacts with oxygen in the molten weld pool and forms stabilized titanium complexes, which promote deoxidation of the steel. Additionally, titanium forms carbide (TiC) and nitride (TiN), which increases the strength of the metal.
Metallurgical Relevance & Risks in Welding
Titanium prevents porosity and increases the toughness of the weld. However, too high a titanium content can make the structure too hard, leading to hot cracking. On the other hand, insufficient titanium can result in fine grains and low toughness.
Workshop Practice & Action Instructions
Titanium is added to low-alloy steels such as 1020 or 4340 to control deoxidation and austenite grain size. A typical titanium content is approx. 0.05 to 0.1 %. The melting time should be long enough for titanium to react fully, but not too long to avoid excessive carbide formation.